Numbers changed after year-end: what to do (and how to stop it happening quietly)

Written by an ACA-qualified finance manager · about the author · Last reviewed 1 July 2026

You’ve filed the year-end and everyone’s moved on - then a figure moves and the accounts you filed no longer match Xero. Here’s how to handle it, and how to make sure it never happens silently again.

What a post-year-end change actually affects

A change in a closed year doesn’t stay in that year - it ripples:

• The filed accounts no longer agree to the live ledger, a problem if anyone re-runs the report.
• This year’s opening balances shift, because they’re last year’s closing balances - your current-year balance sheet inherits the movement.
• Comparatives in the next set of accounts stop matching what was filed.
• The audit, if there is one, now has a difference to explain, and auditors care a great deal about prior-period adjustments.

Because of this ripple, one backdated entry can flag on several periods at once. That’s not a fault in your controls - it’s the same change correctly showing up everywhere it moved a balance.

Step 1: Find what moved

Compare the balance sheet as-at the year-end date now against what you reported at sign-off. If you kept a snapshot of the signed-off numbers, the difference is your answer. If you didn’t, you’re reconstructing from memory - which is exactly why snapshotting at sign-off matters.

Step 2: Find who and when

In Xero, open the affected account and check “History & Notes”, or drill into the transaction. Xero records who created or edited it and when - this turns “the number is wrong” into “this specific entry was backdated on this date by this user.”

Step 3: Correct it, or accept it

Not every change is an error. Ask whether the entry belongs in the closed year. If it’s wrong, reverse or re-date it in the correct open period and note why. If it’s a genuine adjustment and the accounts are already filed, you may need a prior-period adjustment and a conversation about restatement. Document the reason either way. (The mechanics are in when a closed period changes.)

Step 4: Stop it happening silently

Lock dates prevent casual postings into closed years, but remember an admin can lift them and they won’t tell you. A sign-off snapshot is what lets you prove nothing has moved - or catch it the morning it does. The goal isn’t to freeze the past; it’s to make sure nothing changes in it without you knowing. That’s what Postlock does automatically.

Frequently asked questions

Can accounts still change after they’ve been filed?

The filing itself is fixed, but the underlying Xero ledger can still be changed - a backdated bill, a lifted lock, an integration posting historic data. When that happens, the live accounts stop matching what you filed, which affects opening balances and comparatives going forward.

What is a prior-period adjustment?

A correction to figures reported in a previous, already-finalised period. If the accounts are filed, a material change usually can’t just be posted quietly - it may need to be disclosed as a prior-period adjustment or restatement. Document it and speak to whoever signs the accounts.

How do I stop clients or colleagues changing a closed year?

Set and keep lock dates, restrict who has adviser rights, and monitor closed periods against a sign-off snapshot so any change is caught, attributed and explained rather than discovered months later.