Lock your books
A posting lock stops anything being dated into a period you have finished with. Once you set it, nothing on or before that date can be posted, edited or voided — unless someone holds the permission to override it, and if they do, it is recorded.
Use it when a VAT quarter has been submitted, when a year's accounts have been prepared or filed, or any time you need the figures somebody has relied on to stay put.
Before you begin
- Sign in and select your organisation.
- You need the post into a locked period permission — the same one that lets you step over the lock. Moving the line and crossing it are the same authority, so they are not separated.
- The lock is independent of your financial year end. You can lock without setting a year end, and having a year end locks nothing by itself.
Set the lock
- Go to Settings → Accounting Settings and find the Financial year card.
- Under Posting lock, enter a date in Lock everything up to and including.
- Choose Save lock.
The card then reads: "The books are locked up to and including 31 March 2026. Nothing dated on or before that day can be posted, edited or voided."
To lift it, choose Remove the lock.
The date itself is locked. "Locked up to and including 31 March" means 31 March is inside the locked period, not the first open day.
What the lock actually stops
It applies to the date on the entry, not the date you typed it. An expense you enter today but date 1 March is a posting into March, and that is what the lock judges.
It covers everything that reaches your ledger — invoices, credit notes, payments and allocations, bills, supplier payments, spend and receive money, transfers, manual journals, and the automatic entries from online card payments. It also covers changing or removing an existing entry in a locked period, and moving an entry's date into or out of one.
If you are refused, you will see:
This is dated 1 March 2026, and the books are locked up to and including 31 March 2026. Someone with permission to post into a locked period can either change the lock date or post it for you.
See Why can't I post into this date?.
Voiding something inside a locked period
Some voids are refused and some are not, and the difference is genuine rather than an inconsistency. It follows from what the reversal is saying:
- "This should never have happened." Voiding an invoice, credit note, supplier invoice, spend or receive money entry, transfer or journal, or removing a payment allocation, reverses it on its own original date. If that date is locked, it is refused — the whole point is that the locked period's figures do not change.
- "Something new has happened that undoes it." A refund to a customer, and a supplier sending your money back, is dated today, because the money really did move today. Those are not postings into the locked period at all, so the lock does not stop them.
Undoing a posted payment — a customer's or a supplier's — asks you which of the two it is. Inside a locked period the "it was a mistake" option is shown as unavailable and only the refund remains — which is correct, because only one of the two would post into the locked month.
You will usually see this before you click. On a document whose void would be refused, the Void button is shown as unavailable, with the document's date and the lock date beside it — so you can tell at a glance which of the two is wrong. On a new document, the date field warns you the moment the date you enter falls inside the locked period, before you save; if you hold the override, it tells you instead that the posting will be recorded.
The write-off dialog's date field warns the same way. When you allocate a payment to an invoice or bill, the dialog names the date the allocation will be posted on — the settlement date, the later of the payment date and the document date — and warns if that date is locked, as soon as you pick the document.
The document itself is untouched either way. A refused void leaves an issued invoice issued; nothing is left half-done.
Overriding the lock
If you hold the permission, a posting into a locked period simply goes through — there is no extra confirmation step, and the Void button is never greyed out for you. What happens instead is that it is recorded: an audit entry naming the date you posted into, the lock that was in force, and that the override was used. You can see these in Activity and audit history.
Bulk actions never use the override, even for someone who holds it. If you issue several invoices at once and one of them is dated inside the locked period, that one is refused and the rest go through; the results list names it and asks you to open it on its own, where the warning and the choice are yours to make. Each refusal is recorded against the document it was for.
Nothing else about the posting changes.
Refused attempts are recorded too
Every posting the lock refuses is written to the same audit history, naming the date that was refused, the lock in force, who attempted it and — for a practice member working in your books — the practice they were acting for.
This is not there to catch anyone out — being refused is the system working. It is there so that an accountant reviewing the books can see the lock doing its job, and so that a run of refusals against the same period is visible as a sign that the lock was set too early or on the wrong date.
An accountant with delegated access can hold this permission. It is part of the Accountant (external) access profile and deliberately not the Bookkeeper (external) one — closing a year and occasionally reopening it is an accountant's work. Their use of it is recorded against them by name. See Give your accountant access.
Online payment events that arrive inside a locked period
Refunds, card disputes and payouts on online payments reach your ledger on their own, from Stripe, and are dated on the day the money moved. If that day is inside the locked period, the lock refuses them like anything else — and because nobody was there to be told, they are parked for you instead of lost or retried.
The Financial year card shows "2 postings are waiting on this lock" beside the lock, and the Year End page shows the same count. Review them opens the list, which names each posting, why it was refused and the date it carries. For each one you can:
- Replay it. This runs the posting again exactly as it would have run when it arrived, with the lock as it stands now. It never overrides the lock, whoever clicks it — so to book something dated inside the locked period, move the lock, replay, and move it back. A replay that is still refused stays in the list with the reason.
- Dismiss it, with a note saying why. Use this when the movement is already on your ledger another way — a manual journal, a reversal made at Stripe — or when it should not be booked at all. Dismissing books nothing; the note is the record of the decision, and it is kept in the audit history.
Both need the permission to manage accounting settings: the person who decides where the lock sits is the person who decides what to do with what it held back.
What the lock is not
- Not a year-end close. Locking does not finalise anything or move profit into reserves; it only stops changes. Signing a year off is a separate act — see Finalise your year end — and the two are deliberately independent: a finalised year can be unlocked so an accountant can adjust it, and a quarter can be locked long before its year end is done.
- Not per period. One date protects everything on or before it, which is usually what you want: a lock at your last VAT quarter end also protects every year before it.
- Not a substitute for document rules. An issued invoice still cannot be edited whatever the lock says — see What you can and cannot change after posting.