BAS each quarter: a simple routine
A short quarterly routine: get invoices out, check payments, draft the figures in Karven, then lodge with the ATO.
Updated 2026-10-22
This picks up from BAS pre-fill, which explains the figures Karven adds up. Here's a simple routine for each quarter. BAS in Karven is part of the Compliance add-on on the Pro plan.
The routine
| When | What to do |
|---|---|
| Last week of the quarter | Make sure every finished job has been invoiced, so the payments land in the right quarter. |
| First week after | Check your bank account against the payments in Karven. Mark any invoice paid by cash or transfer as paid. |
| Second week | In Tax & ATO, draft the BAS for the quarter. Add GST on your other purchases from your own records. |
| Before the due date | Lodge through the ATO's online services (or have your BAS agent do it). Pay any GST owing. Then Mark as lodged in Karven. |
Quarterly BAS is usually due on the 28th of the month after the quarter ends (the October to December quarter is due 28 February). Check the ATO's dates for your business.
Why the bank check matters
Karven's figures only include payments it knows about. A customer who paid cash, or paid an old invoice without a reference, won't be in G1 until you mark that invoice paid. Unmatched money in your bank is GST you'd otherwise miss.
Lodging
Karven doesn't lodge for you. Log in to the ATO's online services, open your BAS, copy each figure across from the saved BAS in Karven (each one has a copy button) and submit. A registered BAS or tax agent can lodge it for you instead.
Monthly or yearly lodgers
Karven drafts BAS by quarter. If you lodge monthly or yearly, add up the figures yourself or with your bookkeeper.
Keeping records
The ATO expects you to keep business records for five years. Your quotes, invoices and saved BAS figures stay in Karven while your account is open. If you ever close your account, download your data first from Settings → Connections → Data export.
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If anything's unclear or out of date, email info@karven.com.au and we'll fix it.