Accounts · The books

Closed means
closed.

A close is a checklist whose items are ticked off one at a time and by someone. When it completes, the period locks, so a filed month cannot quietly gain a backdated entry three weeks later.

The control most small systems skip. If a closed period can still be posted into, your filed return and your ledger will eventually disagree.

The close

A checklist, signed off item by item.

Your own checklistDefine the steps your close actually has, rather than following a fixed list that half applies.
Line-item completionEach item is completed individually and recorded, so a half-done close is visibly half done.
Complete the closeFinishing is an explicit act on the record — which is what makes "was March closed?" answerable.
The lock

Nothing backdates into a filed period.

Periods lockOnce closed, the period refuses new postings. Corrections go into an open period, where they belong.
Fiscal yearsYears and periods defined as records, so the calendar the business actually runs on is the one the system enforces.
Year end

Balances rolled forward.

Year-end runCloses the year and carries the balances forward, so the new year opens from the old one rather than from a re-entry.
Nearby

Related capabilities.

General ledger · Financial reports · GST returns

A close that holds.

Locked periods are why the return you filed still matches the ledger a year later.