Filing Guides

HMRC CT600 Alternative: Best Free Options for 2026

Accountant Guide: Migrating Clients from HMRC's CT600 Service

Best CT600 Software for 2026: Complete Comparison

Best CT600 Software for Accountants 2025

CT600 software designed for accountants managing multiple clients. Compare features, pricing and efficiency for professional practices.

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.

How to Import Trial Balance to CT600

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

QuickBooks to CT600: Import Your Trial Balance

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

Best Accounting Software UK 2025: Small Business Guide

Compare the best accounting software for UK small businesses. From free options to full-featured packages, find the right bookkeeping solution.

Companies House WebFiling Replacement Guide

Switching from Companies House WebFiling: Step-by-Step

Companies House WebFiling Closing: What Changes in 2027

Companies House Software-Only Filing 2027: Complete Guide

Filing Accounts After April 2027: What You Need to Know

Companies House Accounts Deadlines: Key Dates

Know your Companies House accounts filing deadline. Private companies have 9 months to file. See penalties for late filing and how to avoid them.

Micro-Entity Accounts: What You Can File

Learn what micro-entity accounts are, who qualifies, and how to file simplified accounts to Companies House. Complete guide with 2025 thresholds.

Companies House vs HMRC: Understanding Both Filings

Understand the difference between Companies House and HMRC filings. Learn what you need to file with each, deadlines, and how they work together.

Dormant Company Accounts: Filing Requirements

What accounts must a dormant company file? Learn about simplified dormant accounts, exemptions, and how to file free with TinyTax.

Late Filing Penalties for Company Accounts

What are the penalties for filing company accounts late? Learn about Companies House fines from £150 to £1,500 and how to avoid them.

iXBRL Accounts Explained: What UK Companies Need to Know

Learn what iXBRL accounts are, why Companies House requires them, and how to generate them for your UK company filing.

Confirmation Statement: Annual Companies House Filing

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 Change Your Company Accounting Period

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

Striking Off a Company: Complete Guide

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

CT600 Box 235: Adjusted Trading Profit Explained

CT600 for Property Companies: Complete Guide

CT600 for IT Consultants: Complete Guide

CT600 Box 440: Corporation Tax Payable Explained

The Future of Corporation Tax Filing in the UK

CT600 Box 145: Turnover Explained

Prepare for Software-Only Filing: Complete Guide

HMRC CT600 Shutdown: Your Preparation Checklist

Download Your CT600 History Before HMRC Closes

CT600 Filing Changes Timeline: 2025-2027 Complete Guide

How to Switch from HMRC's CT600 Service: Step-by-Step Guide

CT600 Filing After March 2026: Your Options Explained

UK Corporation Tax Rates 2025/26: Complete Guide

Current UK corporation tax rates explained: 19% small profits rate, 25% main rate, and marginal relief. Calculate your company's tax liability.

Filing Your First CT600: New Company Guide

New company? Learn how to file your first CT600 Corporation Tax return. Step-by-step guide covering registration, deadlines, and common mistakes to avoid.

CT600 Deadlines: When to File Your Corporation Tax Return

Know your CT600 filing deadline: 12 months after your accounting period ends. Learn about payment deadlines and penalties for late filing.

How to File a CT600 Online: Step-by-Step Guide

Learn how to file your CT600 corporation tax return online to HMRC. Step-by-step guide covering everything from registration to submission.

CT600 Box 315: Capital Allowances Explained

Learn how to claim capital allowances on your CT600. Complete guide to Box 315 including Annual Investment Allowance, writing down allowances, and more.

CT600 Box 190: Property Income Explained

Learn how to report rental and property income in CT600 Box 190. Complete guide for UK limited companies with property letting income.

CT600 Box 170: Trading Losses Explained

Made a trading loss? Learn how to report it in CT600 Box 170 and understand your options for loss relief and carry forward.

CT600 Box 165: Trading Profits Explained

What goes in CT600 Box 165? Learn how to calculate and report your company's trading profits correctly for your Corporation Tax return.

CT600 Box 160: Net Trading Profit Explained

What goes in CT600 Box 160? Learn how to calculate and report your net trading profit on your Corporation Tax return.

CT600 Box 155: Gross Profit Explained

What goes in CT600 Box 155? Learn how to calculate and report your company's gross profit correctly on your Corporation Tax return.

10 Common CT600 Mistakes and How to Avoid Them

Avoid these common CT600 mistakes that cost UK companies money and trigger HMRC penalties. Learn what errors to watch for on your corporation tax return.

CT600 Checklist: Everything You Need Before Filing

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

CT600 for Dormant Companies: Do You Need to File?

Does your dormant company need to file a CT600? Learn about HMRC requirements, exemptions, and how to file a nil return for free.

Marginal Relief for Corporation Tax: How It Works

Learn how marginal relief reduces your corporation tax bill if profits are between £50,000 and £250,000. Includes formula and calculator.

CT600 Late Filing Penalties: What You Need to Know

What happens if you file your CT600 late? Learn about HMRC penalties from £100 to 10% of tax owed, plus how to avoid them.

CT600 for Amazon Sellers: Complete Guide

Complete guide to filing CT600 for Amazon sellers in the UK. Learn about FBA fees, VAT, stock valuation, and what expenses you can claim.

CT600 for Buy-to-Let Companies: Complete Guide

Complete guide to filing CT600 for buy-to-let companies. Learn about mortgage interest relief, allowable expenses, and Corporation Tax for landlords.

CT600 for E-commerce Businesses: Complete Guide

Complete guide to filing CT600 for e-commerce businesses. Learn about stock valuation, payment processor fees, digital expenses, and what you can claim.

CT600 for Software Developers: Complete Guide

Complete guide to filing CT600 for software developers. Learn about allowable expenses, R&D tax credits, equipment claims, and contractor considerations.

UTR Number: What It Is and How to Get One

What is a UTR number? Learn about your company's Unique Taxpayer Reference, how to find it, and why you need it for CT600 filing.

Government Gateway: Setup Guide for Companies

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.

Extended Accounting Periods: Filing Two CT600s

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

Directors Loan Account and CT600: What to Report

How directors loans affect your CT600. Understand S455 tax, reporting requirements, and how to handle loans to directors on your corporation tax return.

CT600 Boxes Explained: Understanding Every Field

Complete guide to CT600 boxes and fields. Understand what each box means and what information to enter for your corporation tax return.

Corporation Tax Losses: Carrying Forward and Back

How to use company losses to reduce corporation tax. Learn about carrying losses forward, back, and how to claim loss relief on your CT600.

Capital Allowances on CT600: Complete Guide

How to claim capital allowances on your CT600. Understand AIA, writing down allowances, and which business assets qualify for tax relief.

R&D Tax Credits: Can Your Company Claim?

How UK small companies can claim R&D tax credits. Understand eligible activities, costs, and how to claim through your CT600 return.

HMRC Interest on Late Corporation Tax: Rates and Rules

How HMRC calculates interest on late corporation tax payments. Understand current rates, when interest starts, and how to minimise charges.

Associated Companies: How They Affect Corporation Tax

How associated companies affect your corporation tax rate. Understand the rules, counting methods, and impact on marginal relief thresholds.

Payment on Account: Corporation Tax Instalments

When and how large companies pay corporation tax in quarterly instalments. Understand the thresholds, deadlines, and calculations.