Xero Year End Checklist for CT600

Closing your financial year in Xero is the foundation for a smooth corporation tax return. The figures on your CT600 come directly from your accounting records — so the more complete and accurate your Xero data, the simpler your filing will be.

This checklist covers everything you need to do in Xero at year end, from confirming your accounting period to exporting your trial balance for import into your company tax return.

1. Confirm Your Accounting Period Dates

Before anything else, confirm that Xero has the correct accounting period:

• Go to Settings → General Settings → Financial Settings
• Check the Year End Date matches your company's registered accounting period at Companies House
• If you have changed your accounting period, update this in Xero to match

Filing a corporation tax return for the wrong period is one of the most common mistakes directors make. Your CT600 must cover the same dates as your statutory accounts. For a reminder of your filing obligations and timing, see our guide to company tax return deadlines.

2. Reconcile All Bank Accounts

All bank accounts must be fully reconciled to your year end date. Unreconciled transactions will make your balance sheet inaccurate — and that means your CT600 figures will be wrong.

To check reconciliation status in Xero:

1. Go to Accounting → Bank Accounts
2. Click each account name to open the statement view
3. Check the reconciled balance matches your actual bank statement balance at year end
4. Reconcile any outstanding items

If you have transactions you cannot explain, investigate before marking them as reconciled. Unexplained entries can mean missed income, duplicate invoices, or bank errors — all of which affect your taxable profit.

Key accounts to reconcile:

• Business current and savings accounts
• Director's loan account
• PAYE and National Insurance payments
• VAT payments and reclaims
• Any credit card or loan accounts

3. Review Your Profit and Loss

Run a Profit and Loss report for your full accounting period and check for anomalies:

1. Go to Accounting → Reports → Profit and Loss
2. Set the date range to your full accounting period
3. Review each category for unusual balances

What to look for:

• Revenue: Does the total match your invoices and bank receipts?
• Cost of Sales: Are direct costs categorised separately from overheads?
• Director's salary: Has it been entered through payroll and posted as a wage expense?
• Depreciation: Has your accountant posted the year-end depreciation journals?
• Accruals and prepayments: Have year-end adjustments been posted?

If you use an accountant, they may post year-end journals for depreciation, accrued expenses, and tax provisions directly into Xero. Confirm with them that all adjustments are complete before you proceed.

4. Review Your Balance Sheet

Your balance sheet must balance — total assets must equal total liabilities plus equity. To check:

1. Go to Accounting → Reports → Balance Sheet
2. Set the date to your year end date
3. Confirm the report shows a balanced position

Items to review:

Section	What to Check
Fixed assets	Matches your asset register after depreciation
Trade debtors	Matches outstanding sales invoices
Trade creditors	Matches unpaid supplier bills
Corporation tax payable	Prior year's tax paid and reconciled?
Director's loan	Balance correct and supported by records?
Retained earnings	Prior year profit correctly carried forward?

If your balance sheet does not balance, investigate the suspense account or historical adjustments in Xero before proceeding. A balance sheet that does not balance indicates a bookkeeping error that must be resolved.

5. Post Year-End Journals

Some year-end adjustments are not entered automatically. Depending on your business, you may need to post manual journals for:

• Depreciation — if you are not using Xero's fixed asset register
• Accrued income — revenue earned but not yet invoiced
• Accrued expenses — costs incurred but not yet billed (for example, accountancy fees for the year just ended)
• Prepayments — costs paid in advance that relate to the next period
• Closing stock — if your business holds inventory

If you are unsure whether these apply to your situation, seek advice from an accountant before proceeding. Missing accruals or prepayments can materially affect your reported profit and therefore your corporation tax liability.

6. Lock the Accounting Period

Once all entries and journals are complete, lock the period in Xero to prevent accidental changes:

1. Go to Settings → General Settings → Financial Settings
2. Under Lock Dates, set the Lock Date to your year end date
3. Save

This prevents anyone from editing transactions before the lock date without first removing the lock. Locking the period before exporting your trial balance ensures your export reflects the final, agreed figures.

7. Export Your Trial Balance

Your trial balance is the key report for populating your CT600. It lists every account in your chart of accounts with its closing debit or credit balance at year end.

To export your trial balance from Xero:

1. Go to Accounting in the top menu
2. Select Reports → All Reports
3. Find Trial Balance under the Accounting section
4. Set the date to your year end date and click Update
5. Click the Export button at the top of the report
6. Choose Excel or CSV format

Save the file somewhere you can find it — you will need to upload it when preparing your company tax return.

For guidance on how Xero's account codes map to the boxes on your CT600, see our Xero account mapping guide.

8. Import Into TinyTax

Once you have your trial balance, import it into TinyTax to populate your company tax return automatically:

1. Open TinyTax and start or continue your CT600 for the period
2. Click the Import Trial Balance button in the Profit and Loss or Balance Sheet section
3. Select Xero as your accounting software
4. Upload the CSV or Excel file you exported
5. Review the automatic field mapping and adjust any items that need reclassifying
6. Confirm the import — TinyTax populates the relevant fields

The import significantly reduces manual data entry and the risk of transcription errors. You can adjust individual figures after the import if needed.

9. Gather Supporting Documents

Before completing your CT600, gather any additional information you will need:

• Your company's Unique Taxpayer Reference (UTR) from HMRC
• Details of any capital allowances to claim (Annual Investment Allowance, Writing Down Allowance)
• Details of any director's loans outstanding or written off
• R&D expenditure records if claiming Research and Development tax relief
• Confirmation of any loss relief to carry back or forward

For a comprehensive list of what you need, see our company tax return checklist.

Summary

A clean Xero year end involves confirming your period dates, reconciling all accounts, reviewing your Profit and Loss and Balance Sheet, posting year-end journals, locking the period, and exporting your trial balance. Completing these steps before you start your CT600 means fewer corrections and a much smoother filing experience.

Once your Xero data is accurate and locked, your trial balance gives you everything you need to complete your company tax return with confidence.