Close and reopen the books
Closing the books locks every date on or before a day, so nothing reconciled can change by accident. Here is how to close through your reconciled month, and how to reopen.
What closing does
Closing the books sets a date. Nothing dated on or before it can be added or changed anywhere in ZeraBooks: statement rows, categories, journal entries, bills, invoices, payments and Autopilot's own work. Reports still include those months as they are.
Close the books once months are reconciled, so a late edit can't quietly change numbers you've already reported.
Close the books
The close control sits in the summary line at the top of Reconciliations, next to Reconciled through and the month.
Go to Accounting › Reconciliations.
Click Close books through and the date, for example Close books through June 30, 2026. The date is the last day of the month you're reconciled through. The button appears only when that date is later than the date the books are already closed through.
Read the confirmation: "Nothing dated on or before June 30, 2026 can be added or changed until you reopen."
If the business has a closing password, enter it in Closing password.
Click Close books.

A message confirms "Books closed through June 30, 2026.", and the summary line shows a lock with Closed through June 30, 2026.
Tip: Reconciled through moves forward only when every account with history is tied or finalized for that month, with no gaps. If the button doesn't appear, look for "N months need a look →" and fix those months first.
Reopen the books
In the summary line, click Reopen next to Closed through.
Read the confirmation: "Reopening lets every closed date be edited again."
Enter the Closing password if asked, then click Reopen books.
A message confirms "Books reopened. Every date can be edited again."
Reopen clears the lock completely; you can't reopen only part of the closed period from here. After making your change, close the books again.
Let Autopilot close for you
With Sign off and close months on, Autopilot closes the books through the latest month that is reconciled and signed off on every account, with no open questions, flagged categories or Uncategorized transactions, at least 15 days after it ended. In Cautious mode it asks first, for example "Close the books through June 2026?"
Autopilot's close appears in Done by AI as Closed a month. Undo reopens the books to the date they were closed through before. Autopilot never closes books that have a closing password.
Frequently Asked Questions
What does closing the books do?
It blocks adding or changing anything dated on or before the closing date until you reopen. It doesn't change any numbers.
I get "is in a closed period" when I save. What do I do?
The date you're saving falls on or before the closing date. Reopen the books in Reconciliations, make the change, then close them again, or use a date after the closing date.
Does closing one month lock earlier months too?
Yes. The books are closed through a date, so every date on or before it is locked.
How do I unlock just one month?
You can't from here. Reopen unlocks every closed date. Make your change, then click Close books through again.
What does "Enter the closing password for this business." mean?
The books for this business are protected with a closing password. Enter it in Closing password to close or reopen.
Will closing a month change my reports or exports?
No. Closed months still appear in every report. Closing only stops them from changing.
Learn more about Bank reconciliation software: Every statement proven to tie before the month closes.
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