Spotted a mistake in accounts you've already filed? You can replace them with a corrected version. An amended set of accounts is a fresh filing that supersedes the one before it — Tax Optimiser stamps it with the amendment indicator in the iXBRL, which is how Companies House and HMRC know it replaces an earlier return rather than being a duplicate. This article walks the whole journey: checking the original went through, correcting the figures, marking the accounts as amended, and re-filing with Companies House (and HMRC, if your tax changed).
Amend only after the original has been accepted
Amending is for accounts that have already been filed and accepted. Open your accounting period, go to the Companies House Submission screen and check the original submission shows a green Complete status. If it's still in progress, errored, or was never sent, there's nothing to amend yet — fix and submit the original instead.
Correct the figures first
Marking accounts as amended is a one-way step, so get the numbers right before you do it. Make your corrections the usual way — adjust the trial balance, post a journal, or edit the relevant note — and check the preview shows the figures you expect. If you imported the original numbers from a spreadsheet, see Import a trial balance from a spreadsheet; for a refresher on where everything lives, see A tour of your accounts.
Mark the accounts as amended
The simplest route is straight from the filing screen. On the Companies House Submission screen for a completed submission, click Submit as amended. It does two things in one step: it flags the accounts as amended and starts a fresh submission for the corrected version. Your original submission is kept untouched as history.
You can also flag the accounts on their own from View Accounts: open the Actions list and choose Mark as amended. Either way you'll be asked to confirm, because the iXBRL document is regenerated with the amendment indicator set.
Once amended, the accounts are re-titled “Amended…”, the sidebar shows a green Amended return status, and the preview is banded “Accounts have been set to amend”:
This can’t be undone from the screen, so only mark accounts as amended once the original filing has actually been accepted and your corrections are in.
Re-file with Companies House
If you used Submit as amended, you're already in a fresh submission wizard for the corrected accounts — work through it exactly as you did the first time. (If you flagged the accounts from View Accounts instead, just start a new Companies House submission for the period.) The original submission stays in your history, and you're offered the full or filleted choice again at the Review Document step. For a reminder of what each version contains, see Full or filleted: what gets filed where.
Amend your Corporation Tax return too
If your correction changed the profit, you'll also need to amend the Corporation Tax return you sent to HMRC. You don't set this separately: because the accounts are flagged as amended, the Corporation Tax submission for the same period is automatically treated as an Amended return, and the corrected full accounts re-attach to the CT600 when you resubmit. Re-run the Corporation Tax submission for the period to send the amended figures to HMRC.
That's the full journey — correct, mark as amended, and re-file. For the rest of the year-end, browse the Statutory Accounts guide.