The register is the central page of Books. It shows every transaction across every account and budget item. It can also be used to investigate an account’s balance over time to find missing and extra transactions.
Show a running balance
Pick exactly one account in the Account filter, a new Balance column shows up. The running balance is computed across the whole history of that account — even if you’ve also filtered by date, the values are still correct.
A “—” in the Balance column means “before this account’s opening balance”
When you set an opening balance, that becomes the chronological reset point. Anything before it (typically paid expenses that pre-date when you started using Books) shows “—” in the Balance column. The history is still there for reference — it just isn’t part of the post-opening rolling total.
If you want pre-opening entries to participate in the running balance, set the opening balance to an earlier date or delete the opening balance entry entirely.