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Companies House Proposal to Strike-Off: Why Accounts Filing Is Blocked

Why TinyTax cannot file Companies House accounts while a company is in proposal-to-strike-off, how to clear the status, and filing the CT600 with HMRC in the meantime.

Troubleshooting CT600 Errors

Fix common TinyTax errors including HMRC Error 3001, authentication failures, invalid UTR, and Companies House auth code issues.

Fix CT600 Submission Errors

Fix CT600 submission errors quickly. Common error codes explained with step-by-step solutions for HMRC rejection issues.

Why Your CT600 Shows as Pending or Waiting for HMRC

What a pending CT600 status means, why HMRC can be slow to return a final response, and what to do while you wait for TinyTax to confirm acceptance.

Accounts Not Showing at Companies House After Filing

Filed through us but accounts still missing on Companies House? Learn how to tell whether the success screen you saw confirmed your CT600 or your accounts, how to verify on the public Companies House filing history, and how to file the accounts now if they were never submitted.

Fix CT600 Authentication Errors

CT600 authentication failed when filing? Learn why HMRC rejects your credentials and how to fix authentication errors step by step.

Undoing an Accidental "Filed Elsewhere" Mark on a CT600

Accidentally marked a CT600 period as filed elsewhere? Learn how to undo it yourself from your dashboard, and what to do if the self-service undo fails with a "could not be verified" error.

Why Your Capital Allowances Total Is Higher Than You Claimed

If your Corporation Tax computation shows more capital allowances than you claimed, the same figure has usually been entered in more than one box. How capital allowances are entered, how to fix a doubled or trebled total, and why your tax boxes are blank on a loss.

Why Your Self Assessment Tax Calculation Looks Higher Than Expected: the £500 Dividend Allowance

The £500 dividend allowance is a nil-rate band: dividends within it are taxed at 0% but still use up part of your basic-rate band. A worked example of how this affects your Self Assessment tax, and the common mistake that makes the figure look too high.

Xero Won't Connect? Here's What to Do

Xero connections can fail when Xero's per-app connection limit is reached. Import your trial balance or enter figures manually to file without the live connection.

Why Your CT600 Figures Don't Match Your Accounting Software

Turnover, expenses or tax figures look wrong after importing from Xero, QuickBooks or Sage? The most common cause is a report-period mismatch — here's how to fix it.

Fix Government Gateway Login Errors

Can't log into Government Gateway? Fix common login errors including forgotten User ID, locked accounts, and authentication failures.

Filing Reminders for a Company in Liquidation or Being Struck Off

Fix HMRC Error 1046 (Authentication Failure) on CT600 Submission

CT600 rejected with HMRC Error 1046 (Authentication Failure)? Learn the five causes — wrong credentials, Corporation Tax not enrolled, GOV.UK One Login, lockout, stale password — and how to fix each, including when HMRC confirms sign-on works but submission still fails.

Getting Proof of Your Self Assessment Filing (SA302 and Tax Year Overview)

HMRC Error 1608: Invalid UTR Fix

Getting HMRC Error 1608 when filing CT600? This guide explains why your UTR is being rejected and how to fix the invalid UTR error.

HMRC Error 3001: Business Logic Failure Fix

Getting HMRC Error 3001 when filing CT600? Learn what causes this iXBRL validation error and how to resolve business logic failures.

My Filing Is Stuck or in the Wrong State

Filing stuck, won't move on, or showing the wrong status on TinyTax? How to continue a paused filing, fix period date mismatches, file accounts as well as your CT600, and get a session reset.

Prior Year Balance Sheet Figures Missing, Zero, or Wrong — How to Fix

Why the prior year balance sheet column is blank, zero, or wrong in your accounts — how the figures auto-fetch from Companies House, and how to fix mismatched prior period dates.

Can't See the File or Continue Filing Button on Your Phone

The Continue Filing or Start Filing button isn't showing on your TinyTax Dashboard? On a phone or tablet it sits off the right edge of the table — here's how to reach it.

CT600 Periods Beginning Before 1 April 2015 Must Be Filed on Paper

HMRC's online service cannot accept CT600 returns for accounting periods beginning before 1 April 2015. How to recognise the schema-floor rejection and file the period on paper.

HMRC Determinations — When HMRC Has Assumed a Calculation for an Unfiled CT600

What an HMRC determination (assumed calculation) is, how filing the real CT600 as an original return replaces it, the time limits, and what it means for closing a company.

HMRC Voided or Rejected Your CT600 — Accounting Period Dates Wrong

HMRC accepted your CT600 online but then sent a rejection letter? The accounting period dates usually overlap with HMRC records — here is what to do next.

How to edit your CT600 figures before resubmitting after a filing reset

Need to change a figure on your CT600 before resubmitting after a filing reset? Here is how to use Edit Form to update values and refile without starting over.

Login loop or verification email not arriving on Brave browser

Stuck in a login loop or not receiving verification emails on TinyTax? Brave Shields and strict tracking protection are common culprits — here is how to fix it.

Phone Verification Code During Sign-Up or Payment — Where It Comes From

A phone verification code during sign-up or checkout on TinyTax comes from Stripe Link, not from us. We do not send SMS codes for any account action.

Previous Period Required: Why You Must File an Earlier CT600 First

Seeing a "Previous Period Required" message, or TinyTax won't let you submit your CT600 even though you've paid? You likely have an earlier CT600 to file first — here's why and how to fix it.

Reconnecting MTD for VAT When the HMRC Link Drops

MTD for VAT connection stopped working? Learn why HMRC links expire, how to reconnect through your Government Gateway, and how to tell a credential problem from a VAT period-access problem in TinyTax.

Why Start Filing Looks Blank After Clicking a CT600 Row

What to do if clicking Start Filing on a CT600 row in your TinyTax dashboard appears to show a blank screen with the "We can only track CT600 filings…" message.

HMRC Removed Your Return or Says 'No Original Return Recorded' — Re-filing as a New Original

If HMRC deleted your accepted CT600 (or your amendment was rejected with 'no original return yet recorded'), the return must be re-filed as a new original. Here is how we help.

It Says My Company Is Dormant When I Submit My CT600 — How to Continue as Trading

When your company has no income and only small costs, submitting your CT600 shows a message saying you could file as Dormant. It is optional — click Submit again to continue as Trading.

Accounting Period Not Showing in Dashboard

Accounts Filed Directly with Companies House — Dashboard Status Not Updated

Accounts Shown in Dashboard Look Different From Companies House

Amending a CT600 or Accounts Filed Elsewhere

How to amend a CT600 filed outside TinyTax (we can), and what to do about Companies House accounts filed elsewhere (we cannot — use an accountant or commercial iXBRL software).

Bank Balance Appearing as Expense in Trial Balance Import

Bank Balance Appears Negative in Trial Balance Mapping

Can't File to Companies House — Service Issue or Outage When Submitting Accounts

Why you can't submit accounts or a confirmation statement to Companies House through TinyTax — what a temporary service issue or a wider Companies House outage means, what's affected, and what to do.

Company Address Not Updated After Changing on Companies House

Confirmation Statement Filed Directly with Companies House — Status Still Showing Overdue

Could Not Confirm Figures With Server — What to Do

CT600 Not Showing on HMRC Website

CT600 Shows as Overdue After Filing Confirmation Statement

Director Not Appearing in the SA100 List

Does TinyTax Add Branding to Filed CT600 or Accounts Documents?

Duplicate Company in Your Dashboard: Appears Twice or Shows Overdue

Filed Accounts Manually at Companies House After Submitting via Software

Fix CSRF Token Invalid Errors

Fix Documents Out of Date Error Before CT600 Submission

Fix HMRC Agent Auth Error: NO_PERMISSION_ON_AGENCY

Fix: Accounts or Computations Out of Sync With CT600 Period

Fixing the "Submission Blocked" Error — Tax Computations Out of Sync

Fixing the Could Not Confirm Latest Figures Error

Fixing the Submission Blocked Error

How Long Does Companies House Take to Process Filings?

How to Check Whether You Are Logged In

How to Correct a Submitted VAT Return

How to Restore a Company You Removed from Your Dashboard

Login Locked — Too Many Attempts

Why TinyTax shows "Too many login attempts" and how to get back in — it is a temporary 15-minute security lock, not a permanent block.

MTD VAT Return Not Received by HMRC

No PAYE Reference? What to Enter When You Only Take Dividends

No Start Filing Button for an Older HMRC CT600 Return

Password Reset Page Not Accepting Input on Mobile

Period End Date Warning — Not the Last Day of the Month

Printing or Saving Your MTD VAT Return

Tax ID Field on the Payment Screen

Troubleshooting HMRC Submission Errors

Troubleshooting Payment and Checkout Errors

Unable to Save: Session Data Missing — How to Fix

Verification Email Never Arrives — When Your Mail Provider Is Blocking It

The verification email has not arrived and resending does not help. How to tell when your own mail provider is refusing our messages, and the two ways to get signed up.

What Does a Disabled Period Mean?

What to do if your company's registered office no longer receives post

What to Do When HMRC Says Your CT600 Was Not Received

Why Am I Seeing Review & Submit Instead of a New Form?

Why Are the P&L Totals Showing the Wrong Amount?

Why Companies House Accounts Show as Outstanding When You Join

Why does it say amended return when I have not submitted a CT600?

Why Does My Tax Computations PDF Show Zero Corporation Tax

Why the Form Keeps Sending Me Back (Validation Errors)

Why Your Draft Tax Computation Shows a Different Tax Amount

Do You Offer a Discount or New-Customer Deal?

Does TinyTax offer a discount, promo code, or new-customer deal? One flat published price for everyone, plus how to preview your filing free before paying.

Price for filing an unlimited or large number of companies

How TinyTax handles pricing for accountancy practices with hundreds or thousands of client companies — Portfolio tiers up to 1,000 companies, custom quotes once you're scaling beyond.

Why Was I Charged If I'd Already Filed My CT600?

If you've been charged by TinyTax and believe you'd already filed, this is almost always due to an extended accounting period needing two CT600s. Here's how to check.

Pricing and Plans

Which TinyTax plan is right for you? Compare Solo and Portfolio plans, billing, and what's included.

MTD VAT pricing — tiers for one VRN to 1000

How TinyTax MTD VAT pricing works: £29 a year for one VRN (covers all returns due — current and overdue), with practice tiers up to 1000 VRNs. Direct VRNs and active agent-client relationships count toward the same tier.

Billing and Payment Options

Can I Use Portfolio 50 as a Bookkeeper Without HMRC Agent Registration?

Choosing Plans When You Have Multiple Businesses (Ltd Companies + Sole Traders, Some VAT-Registered)

How to choose the right combination of TinyTax plans when you run multiple businesses — limited companies, sole traders, and mixed VAT registration.

Confirmation Statement Add-On: Per-Company Pricing

How Many Users Can Access My Account (Solo vs Portfolio)

How the Portfolio Company Limit Works

How to Cancel Your Subscription

How to Subscribe to the Dormant Plan

How to Upgrade Your Subscription Plan

Learn how to upgrade your subscription plan to file for more companies. Self-service upgrade with automatic proration.

Portfolio Plans Explained: Where to Subscribe to Portfolio 12, 50, 150 and Larger Tiers

Subscription or One-Off Fee?

VAT on Your Invoices and Subscription Fees

How VAT works on TinyTax subscription invoices, where to find the supplier VAT number, and how to request a corrected invoice if needed.

What Happens After You Pay — Subscription Confirmation and Next Steps

What Is Included in Your Annual Subscription

When Does My Subscription Start?

Why Is the Price at Checkout Higher Than the Advertised Price? VAT Explained

Getting Started with the Dashboard

Learn how to navigate your TinyTax dashboard. Understand status icons, start filings, return to drafts, and use the company details drawer.

What Can You File?

See every company type, filing type, and tax feature TinyTax supports. Check whether your company is eligible.

How to Add a Company to Your Dashboard

Step-by-step guide to adding a company to your TinyTax dashboard — Companies House search, manual entry for charities and registered societies, and what to do if your company isn't listed.

How to Subscribe and Start Filing

Creating an account is free, but you need a subscription to submit filings. This guide explains the difference, how to choose the right plan, and how to start your first filing after subscribing.

Saving Your Work and Drafts

TinyTax saves automatically - no save button needed. Learn how your data is preserved and how to return to unfinished filings.

Trouble Creating Your Account (Sign-Up Errors)

Fix errors when creating a TinyTax account: password mismatch, minimum length, email typos, and the "I'm human" check.

Enrol for HMRC Corporation Tax Online (Government Gateway)

Step-by-step guide to enrolling your company for Corporation Tax on a Government Gateway account so you can file CT600s. Covers the activation code wait, common pitfalls, and what to do if HMRC Error 1046 keeps appearing.

Evaluating TinyTax for a Group with Multiple Companies

Evaluating TinyTax for a group of companies? Here is the overview: multi-entity pricing, migration from Sage/QuickBooks/Xero, how to trial the software, and our support model.

How to Subscribe to and Set Up MTD VAT

Accessing Previous Filings and the Prior Year Fetch Feature

Can an Overseas Accounting Firm Register for TinyTax?

Can an unincorporated association file a CT600?

Can Overseas or Foreign Companies File CT600?

Claiming VAT on Expenses From Before You Registered

How to reclaim VAT on goods and services bought before your VAT registration date, and where to enter the figure in your first MTD VAT return.

Companies House Accounts Filed \u2014 Do I Still Need to File the CT600?

Companies Limited by Guarantee — Filing CT600 and Accounts

CT600 and Accounts: What's the Difference?

CT600 Submission: What Credentials You Need, How Payment Works, and What Happens After

Currency Support — Accounts Must Be Filed in Sterling (GBP)

Do You Need AML Registration to File a CT600?

Does TinyTax Offer a Free Trial?

Does TinyTax Require Accounting Software?

Does a Solo Plan Cover Both HMRC and Companies House Submissions?

Does My Company Need to File a CT600?

Does the Software Comply with CT600, HMRC, and iXBRL Requirements?

Does the Software Work on Mac? Platform and Browser Requirements

Entering Your Accounts Without Accounting Software

Filing a VAT Return When HMRC Owes You a Refund (Repayment Position)

Filing as a Tax Agent for Multiple Companies

Filing for a UK Company as a Non-UK Resident Director

Filing Reminders Explained

Filing Tool, Not Bookkeeping Software

Getting Help and Support

How the Software Works: Cloud-Based, No Download Required

How to Contact Support

How to Edit or Correct a Draft Filing

How to Remove a Company from Your Dashboard

How to Restore an Archived Company

Is This Software Authorised by HMRC?

MTD for Income Tax vs MTD for VAT — What Is the Difference?

Self-Service CT600 and Accounts Filing: What the Software Does and Doesn't Do

Setting Up as an Accountant: Sole Trader and Partnership Practices

Signup Error: We Couldn't Complete Your Signup

Starting a Filing Before Creating Your Account

System Requirements and Browser Compatibility

Tax ID Field on the Payment Screen

VAT Number Field at Checkout — What to Enter

Verifying Your Email Address

What company sizes are supported?

What Financial Data Do I Need to File My CT600?

What Our Self Assessment (SA100) Filing Covers

What the Continue Filing Menu Options Mean

What You Can File

What You Need to File a CT600

When to Sign Up: Subscription Timing and Filing Deadlines

Which Company Types Can Use TinyTax?

Why Does My Dashboard Show Too Early

Year-End Filing Requirements for UK Limited Companies

How to File Your First CT600

Step-by-step guide to filing your first CT600 corporation tax return with TinyTax. Covers company type selection, P&L entry, balance sheet, and HMRC submission.

What documents do I get after filing a dormant CT600?

After a dormant CT600 is accepted, TinyTax stores your accounts PDF and the CT600 form PDF in the dashboard drawer. Here's where to find them and what's included.

How to File a Corporation Tax Return

How to file your corp tax return (CT600) with HMRC. Step-by-step guide for UK limited companies.

What Happens After You Submit

What to expect after submitting your CT600 and accounts via TinyTax. HMRC timelines, confirmation emails, and troubleshooting.

CT600 Filing Checklist

Complete CT600 checklist for UK companies. Everything you need to gather before filing your corporation tax return. Avoid mistakes and delays.

Entering Brought-Forward Losses on a First CT600 for Clubs and Associations

Clubs, societies and associations not registered at Companies House can carry forward losses from earlier years even on their first CT600. Where to enter trading and property (Box 250) brought-forward losses.

How to Pay Corporation Tax

Step-by-step guide to paying your corporation tax to HMRC. Payment methods, deadlines, and what happens if you pay late.

Associated Companies and Marginal Relief

How associated companies affect your corporation tax thresholds and marginal relief calculation in TinyTax.

Box 618 on Your CT600 and How Close Company Status Is Handled

Box 618 on the CT600 is "No – neither" in the Exporter Information section, not a close-company indicator. Here is what each close-company-related box on the CT600 actually does and what to tick.

CT600 Amendments

Need to correct your CT600 after filing? Learn when you can amend, the 72-hour wait, and how to do it in TinyTax.

Filing a Late CT600

Yes, you can file a late CT600 with TinyTax. Here's what penalties apply and how to submit.

Mark a Prior CT600 as Filed Elsewhere

Mark previous CT600 periods as filed elsewhere if you used an accountant or other software. Unblock current filings without refiling old periods.

Set Up Your Government Gateway

How to set up Government Gateway for your UK company. Step-by-step guide to creating your HMRC online account and enrolling for Corporation Tax services.

Common Expense Categories

Where do your business costs go on the P&L? A guide to the four expense categories in TinyTax's micro-entity format.

Property Company Accounting

How to file a CT600 for a property company with TinyTax. Covers rental income, property expenses, and Box 170.

Capital Allowances and AIA

Claim tax relief on business equipment with Annual Investment Allowance (AIA). Learn what qualifies, limits, and how to enter capital allowances in TinyTax.

Capital Gains and Disposals

How to report chargeable gains on your CT600. Covers Box 210, supported company types, and workarounds in TinyTax.

Director's Loans and the CT600A

What is a director's loan account, and when do you need the CT600A? Covers DLA, S455 tax, and what TinyTax supports.

Extended Accounting Period: Why You Have Two CT600s and How They Are Submitted

Accounting period over 12 months? Learn why you need two CT600 returns, how to split profits correctly, and which deadlines apply.

How to Change Your Accounting Period

How to change your company's accounting period. Understand the rules for shortening or extending your financial year with Companies House.

Why the CT600 Has No Balance Sheet — and Where Your Figures Live

The CT600 corporation tax return does not contain a balance sheet — it sits in your accounts. Where to enter balance sheet figures in TinyTax, and why the total rows are read-only.

How Losses Brought Forward Work

Use previous year losses to reduce corporation tax. Learn how brought forward losses work, where to enter them, and how they offset profits.

Splitting AIA Across an Extended Accounting Period

Filing an accounting period longer than 12 months? Learn how TinyTax apportions your Annual Investment Allowance across the two CT600s, why the default is pro-rata, and how to override the split.

Told HMRC Your Company Was Dormant? What That Does (and Doesn't) Change About Your Accounting Period

Notifying HMRC of dormancy does not shorten your Companies House accounts period. What it can change is your Corporation Tax period — here's how to check and file correctly.

CIS Deductions

How Construction Industry Scheme (CIS) deductions work on the CT600. Covers Box 515 and current limitations in TinyTax.

Does This Software Support Marking a CT600 as Containing Estimated Figures (Box 55)?

Whether TinyTax's CT600 filing supports the HMRC Box 55 estimated-figures indicator and a freeform disclosure note.

Exchange Rate Differences

Where to enter exchange rate gains and losses on your CT600 in TinyTax. Covers FRS 105 treatment.

Filing One Part of a Longer Period of Account with Custom Dates

How to file a single CT600 for one part of a longer period of account using custom dates, why Box 85 is ticked instead of Box 80, and why no accounts are attached to that return.

How do I correct a wrong UTR before submitting my CT600?

If you entered the wrong UTR, you can correct it on the Review & Submit page before sending your CT600 to HMRC. Here's how.

Software-Only Filing — What Changed and What You Need

Both free government filing services closed on 31 March 2026. What software-only filing means for your CT600 and your Companies House accounts, and what you need to get set up.

Switch from Companies House WebFiling

Guide to switching from Companies House WebFiling to commercial software. WebFiling for accounts closed on 31 March 2026.

Switch from HMRC's CT600 Service

Step-by-step guide to switching from HMRC's free CT600 filing service, which closed on 31 March 2026, to commercial software.

Can I File My CT600 by Post? (TinyTax Is Online-Only — Here's When Paper Filing Applies)

TinyTax files CT600s electronically to HMRC. Paper filing is only allowed in limited cases — pre-April-2015 periods or an HMRC-agreed exemption. What to do in each case.

HMRC's CATO Service Has Closed: Where Your Old CT600 Returns Are Now

HMRC's Company Accounts and Tax Online (CATO) service closed on 31 March 2026. Where copies of your previously filed CT600 returns, computations and accounts actually are now, and how to get them.

My CT600 Does Not Show My Loss — Why the Profit Box Is £0 and Where the Loss Appears

If your company made a loss, your CT600 shows £0 taxable profit and the loss appears as a loss carried forward. On an extended period the loss is split across two returns.

Accounts Corporation Tax Differs From the Calculated CT600 Tax

Agent Credentials vs Company Director: Filing CT600 for Multiple Companies

Amending a CT600 to a Nil Return

Amending a CT600: How to correct a Corporation Tax return

Are Accounts Submitted to HMRC with the CT600?

AVEC and Creative Industry Tax Credits — What is Supported

Balancing Charges on Asset Disposals

BID Levy Income and Corporation Tax: What to Enter on the CT600

Called Up Share Capital Not Paid: How to Enter It on the Balance Sheet

Can I add a note or comment to my CT600 return?

Can I attach a PDF to my CT600 submission?

Can I File as Dormant if There Were Transactions During the Year?

Capital Allowance Schedules and Pool TWDV Records

Capital Allowances for Company Cars on a CT600

Capital Allowances: Disposal Proceeds When an Asset Has Outstanding Finance

Charity CT600: Short HMRC Period and What TinyTax Generates

Claiming an HMRC Corporation Tax Overpayment Repayment

How HMRC repays overpaid Corporation Tax. Why a credit arises, how to register bank details so the money is paid to your company, and what to do if nothing arrives.

Close Investment-Holding Company (CIHC) and Corporation Tax

Confirming a CT600 Amendment Was Accepted and Downloading Updated Documents

Corporation Tax in Your Accounts — P&L and Balance Sheet

Creative Industry Tax Relief and CT600P

CT600 Accepted but Not Showing in HMRC Business Tax Account

CT600 and Companies House: Two Separate Filings

CT600 Box 115 and CT600E Supplementary Pages

CT600 Box 3 (Tax Reference) Blank in Draft Documents

CT600 Fields Not Included (Exporter, Bank Details, Expenses)

CT600 Fields That Are Automatically Calculated — Profit Before Tax and Others

CT600 Prior Year Period Dates and Comparison Figures

CT600 Profit and Loss — Other Charges (Contractors, Overseas Costs, Professional Fees)

CT600 shows as overdue but HMRC never sent a notice to deliver

CT600 Values Missing or Blank — Common Causes and Fixes

CT600E Assets Schedule — Boxes E130 to E190

CT600E: What to Enter for Charity Number and Repayment Reference

Director Remuneration and Corporation Tax — Allowable Expenses

Director's Loan Accounts — Balance Sheet and CT600 Treatment

Dividends and Corporation Tax: Dividend Income from Group Companies, Box 620, and Trial Balance Import

Do I Need to File a CT600 if I Have Already Paid Corporation Tax?

Do I Need to Fill In the Northern Ireland Boxes on My CT600?

Registered in Northern Ireland? Find out why the CT600 Northern Ireland rate boxes are optional and usually not needed.

Does TinyTax act as my HMRC agent?

Double Taxation Relief and Foreign Withholding Tax

Downloading Your Filed Documents After Submission

Entering Bad Debts in Your CT600: Which Field to Use

Entering Foreign Currency Figures (Multi-Currency)

Entering Prior Year Figures When Previous Returns Were Filed Elsewhere

Entering Your Company Expenses on the CT600 P&L Form

Entering Zero Figures: Why Fields Show as Blank

Extended Accounting Period: Why Your CT600 Figures Don't Match What You Entered

Fair Value Adjustments and Corporation Tax

Filing a CT600 as a Tax Agent

Filing a CT600 for a Historical or Prior Period

Filing a CT600 for a Holding Company

Filing a CT600 When Your Company Has Expenses But No Income

Filing a CT600 When Your Company Has Only Savings or Interest Income

Filing a CT600 When Your Company Only Traded for Part of the Period

Filing a CT600 When Your HMRC Period Differs From Companies House

Filing a Final CT600 When Closing Your Company

Filing a Final CT600 When Closing Your Company

Filing a Prior Year or Late Self Assessment Return

Filing Accounts for Flat Management and Freehold Companies

Filing After Changing Your Accounting Reference Date

Filing an SA100 as a Tax Agent

Filing CT600 After Submitting Accounts Separately

Filing CT600 and Accounts for Companies with Digital Assets

Filing CT600 and Companies House Accounts at the Same Time

Filing CT600 as a Tax Agent

Filing CT600 for a Charitable Company

Filing CT600 and CT600E for a charitable company. Why TinyTax handles the HMRC side (CT600 + CT600E supplement) but not the Companies House statutory accounts (which require Charities SORP).

Filing CT600 for a Historical Period Not Showing on the Dashboard

Filing CT600 to HMRC When Accounts Already Filed at Companies House

Filing Deadlines and Catching Up on Late Accounts

Filing for Dissolved or Struck-Off Companies

Filing for Multiple Accounting Periods Under One Subscription

Filing Periods Ending After 31 March 2026 — Now Supported

Filing Your CT600 Twice — Will HMRC Charge Again?

Filling In Your CT600 Figures — Profit, Expenses, and What Goes Where

First Accounting Period Not Showing on Your Dashboard

Flat Rate VAT Benefit and the CT600 — Where to Enter It

Furnished Holiday Lettings (FHLs) and Corporation Tax

Government Gateway and Corporation Tax Enrolment

Grant Income and Corporation Tax for UK Limited Companies

Group Relief and CT600 — Does TinyTax Support It?

HMRC Says My CT600 Was Not Allocated to a Period — Should I Resubmit?

What to do when HMRC's Corporation Tax helpline tells you a CT600 wasn't allocated and you need to resubmit — common after an extended first accounting period.

HMRC Says You Owe a Return for a Period Missing From Your Dashboard

What to do when HMRC says a CT600 is outstanding for an accounting period that does not appear on your dashboard — including short gap or stub periods of a few days.

HMRC Shows an Amount Due After Filing — Prior Credit Applied

HMRC Shows No Outstanding Period Balances: Do You Still Need to File a CT600?

How Long Does HMRC Take to Accept a CT600?

How Marginal Relief is Calculated for Short Accounting Periods

How to Access Your Previous CT600 Submissions

How to Amend a CT600

How to file an amended CT600 when HMRC already has your return. Fix errors in figures, correct information, or respond to HMRC queries.

How to Check if HMRC Has Registered Your Company for Corporation Tax

How to Check Whether Your CT600 Was Successfully Submitted

How to Edit Your Figures Before Submitting

How to File a Dormant CT600

File your dormant company CT600 with TinyTax. Learn what counts as dormant, which fields to complete, and the difference between HMRC and Companies House dormancy.

How to Prepare Your Financial Figures for CT600 Filing

How Your CT600 Is Submitted to HMRC — Format and Verification

How Your Filing Reaches HMRC and Companies House

I Don't Have a UTR — Is My Company Registered for Corporation Tax?

Including Income Tax Deducted at Source on Your CT600

Intangible Assets and Tax Relief on Amortisation

IRmark and Proof of CT600 Filing

Is Off-Payroll Working (IR35) Turnover Declared on the CT600?

Loss Carry-Back Claims

Missed Capital Allowances in a Previous Year

MTD for Corporation Tax — Quarterly Updates

Mutual Trading Income for Clubs \xe2\x80\x94 What to Enter on the CT600

Non-Trade Loan Relationship Deficits — Boxes 260, 263 and 795

Non-Trade Loan Relationship Deficits on the CT600 (Boxes 260, 263 and 795)

Where to enter a non-trade loan relationship deficit on the CT600, the difference between Box 230 and Box 260, why Box 795 may be smaller than the figure you entered, and how to carry the whole deficit forward instead of setting it against this period.

Non-Trading Income and Disposal Profits on Your CT600

P&L Account Analysis and CT600 Filings

P&L and Balance Sheet: Manual Entry vs Import

Paying Corporation Tax After Your CT600 Has Been Accepted

Period Spans Two Financial Years — Profits Apportioned

Periods Ending After 31 March 2026 Can Now Be Filed

Pre-Trading Company CT600: How to Handle Setup Costs

Preview Is Not the Same as Submitting — How to Complete Your Filing

Clicking View Draft Submission generates a preview but does not file your return. Learn how to complete your CT600 and accounts submission.

Prior Year Boxes on CT600 After a Split Accounting Period

Profit and Loss Line Item Labels Explained

Property Company P&L: Understanding the Expense Categories

Property Income Box 190 is Blank — How to Enter Property Rental Income

Qualifying Charitable Donations and Box 305 on the CT600

R&D Tax Credits (SME, RDEC and ERIS) — What We File and What We Don't

Regenerating Filed Documents That Show 'Document Unavailable'

Retained Earnings in the Balance Sheet

Split-Period CT600: Box 85 and Box 155 Explained

Staff Costs and Directors Remuneration in the CT600 PL

Stamp Duty Land Tax in Your Company Balance Sheet

Starting Your Next CT600 After the Previous Year

Structures and Buildings Allowance, Land Remediation Relief, and Other Specialist Reliefs

Taxable Profit vs Accounting Profit — Why Your CT600 May Show Tax When Accounts Show Zero

The Filing Amended CT600 Banner Explained

Trading Loss Carry-Back on CT600

Training Expenses Mapped as Disallowed in Trial Balance Import

Turnover vs Capital Introduced: What Counts as Trading Income

Turnover, Refunds, and Negative Values Explained

UK Property Business Losses on the CT600

Understanding the P&L Table — Income, Expenses and Prior Year

Understanding Your Tax Calculation

Understand how corporation tax is calculated from your accounting profit. Explains key CT600 boxes, disallowable expenses, capital allowances, and tax rates.

Unsupported Tax Features

TinyTax is designed for straightforward filings. Learn what advanced CT600 features aren't supported and how to work around limitations using existing fields.

Using iXBRL Accounts with Other Filing Software

UTR Not Showing on CT600E PDF

What Does "No Taxable Profits" Mean?

What Gets Submitted to HMRC for an Unincorporated Association?

What Happens If I File a CT600 to HMRC Twice

What to Do When HMRC Says Your CT603 Notice Is Not in Their System

Where to Enter CJRS (Furlough) Income on Your CT600

Where to Enter the Company UTR in TinyTax

Which CT600 Boxes Do Tax Adjustments Feed Into

Why TinyTax generates accounts for a charity CT600 filing

Why Are Some CT600 Boxes Empty or Zero?

Explains why many CT600 boxes show as zero or empty in the preview. Covers which boxes apply to trading vs property companies, loss periods, and Box 3 (UTR).

Why Box 329 Is Ticked on a Loss-Making CT600

Why Does My CT600 Show a Different Tax Amount to My Tax Calculation?

Why Does the CT600 PDF Still Show Old Figures After an Amendment?

Why Is Corporation Tax Showing When I Have No Profit?

Why Is My Trading Profit the Same as My Turnover?

Why Is the CT600 and Accounts Option Greyed Out?

The "CT600 and Accounts" option is greyed out when accounts are already on record at Companies House — it controls only the Companies House leg. HMRC still receives your accounts (iXBRL profit and loss and balance sheet) on a CT600-only filing, and how to amend if HMRC says accounts were missing.

Why the Computations PDF Shows a Different Loss Figure to the Form

Why the Personal Allowance Does Not Apply to Your CT600

Why Your CT600 Shows Outstanding After Filing Directly with HMRC

Why Your Dashboard Still Shows the Previous Accounting Period

Why Your HMRC Account Does Not Show Your Corporation Tax Filing Yet

Your First CT600 After Dormancy

Your first CT600 after dormancy covers a different period than you expect. Learn how CT600 periods work when transitioning from dormant to trading.

Inviting Your Accountant or a Team Member to Your Account

How to invite your accountant or a team member to your TinyTax account, why existing users receive no invitation email (access is instant), and what invited accountants can see.

Billing, Refunds & Cancellation: Request a Refund or Get Your Money Back

How billing works on TinyTax. Pay-per-filing pricing, refund policy, and cancellation.

Change Your Email, Password, Organisation Name, and Other Account Details

How to change or correct your TinyTax account details — your name and email, your organisation name, team members, companies, and registered address — plus what to contact support about, including duplicate companies and data deletion.

Adding and Managing Team Members

Managing Your Email Notification Preferences

Sharing One Account or Subscription Across Multiple Companies

Export Your Xero Trial Balance

Step-by-step guide to exporting your trial balance from Xero. Get your accounts ready for CT600 filing with TinyTax.

How to Import Your Trial Balance

How to import your trial balance into CT600 software. Speed up corporation tax filing by importing from Xero, QuickBooks, or CSV files.

Xero to CT600: Import Your Trial Balance

How to export your trial balance from Xero and import it into CT600 software. Step-by-step guide for faster corporation tax filing.

QuickBooks to CT600 Guide

How to export your trial balance from QuickBooks and import it into CT600 software. Step-by-step guide for UK corporation tax filing.

FreeAgent Category Mapping

How FreeAgent categories map to TinyTax's P&L fields. Includes trial balance import instructions.

FreeAgent to CT600 Guide

How to use FreeAgent accounts for your CT600 filing. Export your trial balance and complete your corporation tax return with TinyTax.

Partnership Programmes — Referral, White-Label, and Filing API

How to partner with TinyTax: three programmes for accountants, software vendors, and white-label resellers. Referral commission, white-label setup, and Filing API integration.

Sage to CT600 Guide

How to use Sage accounts for CT600 filing. Export your trial balance from Sage 50 or Sage Business Cloud and file with TinyTax.

Wave to CT600 Guide

How to use Wave Accounting for CT600 filing. Export your financial data from Wave and file your corporation tax return with TinyTax.

CT600 from Spreadsheets

How to file CT600 when you use Excel or Google Sheets for bookkeeping. Prepare your spreadsheet accounts for corporation tax filing.

Developer API: Authentication and Getting Started

Trial Balance Import: Understanding Category Mapping

Small Company Accounts (FRS 102 Section 1A)

How TinyTax automatically detects whether your company needs micro-entity or small company accounts, and what's different.

Micro-Entity vs Small Company Accounts

When does TinyTax use micro-entity (FRS 105) vs small company (FRS 102 Section 1A) accounts? Covers thresholds and auto-detection.

Managing Directors on Your Filing — Why They Sync From Companies House

Directors on your TinyTax filing come from Companies House and cannot be deleted in the app. To remove a director, file their resignation at Companies House first.

What Is a Confirmation Statement?

What is a confirmation statement? When it's due, what it contains, and how to file. Your guide to this annual Companies House requirement.

How to Strike Off Your Company

How to close your limited company by striking off. Understand the process, requirements, and alternatives to voluntary dissolution.

Accounts Approval Date and Prior Year Comparatives — What to Expect

Accounts Filing for Community Interest Companies

Accounts Only Filing — Companies House Without CT600

Adding Notes to Your Company Accounts

Average Number of Employees in Your Accounts

Balance Sheet Equity — Other Reserves and Capital Contribution Reserve (FRS 105)

Balance Sheet Fields — What Figures You Need

Balance Sheet Fields — What to Enter in Each Category

Can I File Company Accounts on Paper with Companies House?

Changing the Accounts Signing Date (Approval Date)

Charity Accounts: Why They Show Accruals Basis (and What to Do)

Choosing FRS 102 Accounts When Your Company Qualifies as Micro-Entity

Companies House Accounts: Micro-entity and Small Company Formats

Companies House Auth Code

Find your Companies House Authentication Code for filing accounts. Learn where to locate it, how to request a new one, and fix common auth code errors.

Companies House Authentication Code — Security and iXBRL Download

Companies House Filing Changes from April 2028 — What TinyTax Users Need to Know

Companies House Presenter Account and Third-Party Software

Companies House Rejected Accounts: Accounting Reference Date Mismatch (Error 3081)

Comparative Column Shows Year to Instead of Correct Period

Corporation Tax Creditor in the Balance Sheet

Corporation Tax in Your Accounts: Where It Appears in the Profit and Loss

Corporation Tax on Your Balance Sheet — Why It Shows as a Creditor

Corporation Tax Refund — How to Record It in Your Accounts

Deferred Income in Company Accounts — Where to Enter It

Dividends Paid — Where They Appear in Your Accounts

Do You Need to Download and Sign Your Submitted Accounts?

Dormant Accounts When There Is a Director Loan on the Balance Sheet

Dormant Company Accounts With Assets or Liabilities

Downloading Your Accounts and Filing Documents

Entering a Revaluation Reserve in the Trial Balance

Entering Balance Sheet Figures — Assets, Liabilities, and Sign Conventions

Entering Closing Stock and Inventory in Your Balance Sheet

Entering Expenses in the Profit and Loss Section

Entering Fixed Assets and Depreciation in Your Accounts

Entering Old Accounts with AC Code References

Entering Your Figures Without a Trial Balance

Filing LLP Accounts with Companies House

Filing Micro-Entity Accounts (FRS 105) to Companies House

Final Period Accounts — Transactions After Cessation Date

Free and Low-Cost Software for FRS 102 Small Company Accounts

Need FRS 102 Section 1A accounts instead of micro-entity? Companies House WebFiling closed for accounts on 31 March 2026 — here are the routes that still work, including the free paper option.

FRS 105 Micro-Entity Accounts — Prepayments and Current Assets

How TinyTax Generates Your Accounts — Form Entry and iXBRL Output

How Accounts Filing Works: Entering Figures, Signing, and What to Expect

How to Amend Companies House Accounts

How to Complete the Accounts Section of Your Filing

Is My Profit and Loss Account Published at Companies House?

Your profit and loss account is never filed on the public Companies House register. Filleted accounts, what is public, and why the form still asks for the figures.

Is My Trial Balance Submitted to HMRC or Companies House?

Micro-Entity Accounts: What Is Filed with HMRC and Companies House

Negative Balance Sheet: What It Means and How to Enter the Figures

Overriding the Tax Charge in Your Income Statement (Deferred Tax)

Post-Balance-Sheet Events: Dividends Declared After Year End

Prior Year Figures When Filing Your Next Return

Prior Year Income Statement (P&L) Comparative Figures — How to Enter Them

Prior Year Restatement Label and Font Options in Accounts

Prior Year Tax on Profit in Comparative Accounts

Prior-Period Tax Adjustment in Annual Accounts (P&L Charge vs Balance Sheet Creditor)

Showing Grant Income Separately from Turnover in Your Accounts

Switching from FRS 102 Section 1A to FRS 105 Micro-Entity Accounts

VAT Balance on the Balance Sheet

What Format Are Accounts Filed with Companies House?

What Gets Filed to Companies House

When Are Companies House Accounts Due? (9-Month Deadline Explained)

Why Accounting Policies Appear in Micro-Entity Accounts

Why Are Prior Year Comparative Figures Showing as Zero?

Why Are Some Figures Shown in Red in the Draft Accounts PDF?

Why Does My Property Company's Full Accounts Show Turnover Instead of Rental Income?

Why Does the Dashboard Still Show Accounts as Overdue After Filing?

Company types TinyTax can't file for

Which UK company types TinyTax cannot file CT600 or accounts for — PLC, limited partnership, overseas, private unlimited, sole trader — and what to use instead.

Does this service support VAT or PAYE?

What TinyTax does and doesn't cover: CT600, Companies House accounts, and confirmation statements yes; VAT and PAYE no. Where to go for VAT (MTD software) and PAYE (payroll software) filings.

Can I file for a charity or community benefit society?

Filing CT600 for charities, CASCs, mutual societies, or community benefit societies. What's supported (including CT600E for manual-entry charities), what isn't, and how PDF accounts are attached. Includes the 'no Start Filing button on dashboard' workflow for societies.

Why a Registered Overseas Entity Can't File a CS01 Confirmation Statement

If your company number starts with OE it is a registered overseas entity — it files an Overseas Entity Update Statement, not a CS01 confirmation statement, and TinyTax cannot file it.

Two Logins With Companies Split Across Them

Ended up with two logins and your companies split across both? TinyTax accounts cannot be merged for security reasons — learn how to consolidate onto one login instead.

Reporting a Security Vulnerability (Responsible Disclosure)

How to report a security issue on TinyTax. What to include, our response timeframes, and our position on paid bug bounties.

How do I file for a CIC or CLG?

Filing CT600 and accounts for Community Interest Companies (CICs) and Companies Limited by Guarantee (CLGs). What's supported, including CT600E carve-out for manual-entry charities.

Adding a Sole Trader VAT Client to Your Account

Applying a Discount or Promo Code

Downloading Your Accounts and Profit and Loss as a PDF

How do I connect Xero?

How to Cancel Your Account and Delete Your Data

How to Contact Companies House Directly

How to Edit or Change Your Accounting Period Dates

How to enter custom accounting period dates using the "Need to file for different dates?" link when your CT603 shows different dates.

How to File Final Returns When Your Company Has Ceased Trading

How to file final CT600 + accounts when closing a UK limited company. Covers strike-off ordering, custom date periods, and the pre-DS01 case (filing CT600 before applying for strike-off).

SA100 Employment Section — Which Company Is Pre-filled and How to Change It

Student Loan Already Deducted Through PAYE — Entering Your P60 Figure in Self Assessment

Why TinyTax Emailed You About a Figure After Filing

Explains the automated check that reviews submitted CT600 figures for possible data entry slips, such as a cost entered as a negative number, and why we email you rather than correcting it ourselves.

API Pricing and Billing

How API filings are billed — included with your Portfolio subscription, with no per-filing fee or separate balance.

Data processing, security, and DPA

Director Identity Verification for Confirmation Statements

Companies House now requires every director to verify their identity before a confirmation statement (CS01) can be filed. How verification works, where to enter the personal code, and how to fix the "all active directors must verify" and director name-format rejections.

How to file your confirmation statement (CS01)

HMRC Declared My Company Dormant — Do I Still Need to File a CT600?