By Manvinder Sidhu, Co-founder, Ezyiah
Short answer: Bank feed problems cause BAS errors because of what happens while the feed is down, not because of the outage itself. Transactions get imported by CSV to keep work moving. When the feed reconnects it backfills the same days, and dates, descriptions or GST codes come in differently from the feed. Reconciliation still balances, so nobody notices until the BAS figures don't line up weeks later. The fix is to control the import window, record what was imported, and check the overlap as soon as the feed recovers.
Why do bank feeds drop out around BAS time?
A bank feed is a chain. Transactions move from the bank, through a connection provider, into your accounting software, and an interruption anywhere along that chain pauses the feed. Xero explains how its feeds work in About bank feeds and posts known disruptions on status.xero.com. Outages aren't more likely around BAS. They just hurt more then, because the due date doesn't move and the team can't afford to wait.
Why don't errors go away when the feed reconnects?
When a feed recovers, most teams assume the risk has passed. It hasn't. Three things stay behind:
- Overlap. The feed backfills from the last point it's sure of, which is often earlier than where your CSV started. The same payment can arrive twice.
- Inconsistent coding. A line from a CSV often defaults to a different tax rate from the matching feed line. One copy carries GST and the other doesn't.
- Lost context. Once imported lines are reconciled and blended with feed data, nobody can tell which lines came from a file or why a description was edited.
None of these break reconciliation. Reconciliation checks that the ledger matches the bank, not that the GST treatment is right. That's why the problem first appears at the BAS, which builds from GST codes by reporting period.
How do you stop a feed outage turning into a BAS error?
- Check before you import. Confirm the feed's last transaction date and import only the days after it.
- Log the import. Record the account, date range and file, so the overlap window is known when the feed returns.
- Check the file, not just the total. Look at date format, sign, description length and GST codes before you reconcile.
- Reconcile the overlap deliberately. When the feed recovers, compare its first days against the import and remove duplicates before you code anything new.
- Review GST early. Run a GST report for the period well before the due date, not on the last day.
If an error does reach a lodged BAS, the ATO allows many GST errors to be corrected in a later BAS within time and value limits. See Fixing BAS mistakes or making adjustments and our guide on how long you can amend a BAS.
How Ezyiah handles this
Ezyiah is an AI bookkeeper that keeps its own double-entry ledger, so there's no hand-off between a review tool and your accounting file. It pulls live bank feeds daily on every plan. When there's a gap, you can upload CSV or PDF statements into the same books and Ezyiah reconciles them with AI. AI Memory applies your past coding decisions, Scan Similar Transactions fixes a pattern across the file in one go, and the Ezyiah Assistant panel shows an activity trail of what changed. BAS, P&L, Balance Sheet and the General Ledger all build from those books, and your accountant reviews and approves the BAS before lodgement.
See how that compares with Xero, MYOB and QuickBooks, or see how it works for accounting firms.
Frequently asked questions
Can reconciliation balance while the BAS is still wrong?
Yes. Reconciliation confirms the ledger matches the bank. The BAS is built from the GST codes on each transaction, so a duplicate that has been matched, or a line with the wrong tax rate, can reconcile perfectly and still be wrong on the BAS.
How do I find errors left behind by a feed outage?
Start with the dates the feed was down. Compare the imported lines against the backfilled feed lines for that window, check the GST code on each copy, and look for descriptions that were shortened or edited.
Is one bank's feed more reliable than another's?
We don't have reliable data to rank banks, and you shouldn't plan around it. Any feed can pause. Plan so that a pause doesn't change your numbers.
