What Documents Should I Give My BAS Agent? A Quarterly BAS Checklist for Australian Businesses

Last updated: 25 October 2026.

The fastest way to a stress-free BAS is to give your BAS agent complete, organised information early. Most delays are not caused by the BAS itself. They come from missing invoices, unreconciled bank accounts and unanswered questions in the week before the due date.

This checklist sets out what a BAS agent typically needs from a small Australian business, based on the ATO’s record-keeping rules, with a suggested timeline. It was checked against primary sources on 25 October 2026 and is general information, not advice about your specific situation.

The short version: give your agent authority to act, access to your accounting software and bank feeds, valid tax invoices for what you sold and bought, your bank and card statements, payroll and super records if you have staff, and answers to any questions about unusual transactions. If your books are in good order, the BAS is mostly a review.

Step 1: authorise your agent

Your agent cannot lodge for you until you have given them authority. The ATO says all types of entities with an ABN, other than sole traders, must nominate a registered agent when engaging a new one. You do this in Online services for business, using your agent’s registered agent number. Your agent cannot complete the nomination for you, they are not automatically notified, so tell them when you have done it. They then have 28 days to add you as a client, and you can extend a nomination once for another 28 days. If you have not set up Online services for business before, allow extra time: the principal authority for the business must set up a Digital ID (myID) and link it to the business in Relationship Authorisation Manager first.

Also give your agent your ABN, your GST accounting method (cash or non-cash) and your reporting cycle (monthly or quarterly), as they affect how the BAS is prepared. The ATO’s GST accounting method page explains how each works.

Step 2: give access, not just paper

  • Accounting software access. Invite your agent to your file (for example in Xero or MYOB) so they can see transactions directly instead of working from exports.
  • Bank and credit card feeds connected for every account the business uses, or statements if a feed is not available.
  • Payroll system access if payroll is separate from your accounting software.

The ATO recommends digital record keeping where possible, and business.gov.au says the ATO accepts electronic images of paper records if they are a true and clear reproduction of the original. So a clear photo of a receipt can be enough, provided it follows the rules.

Step 3: sales records

The ATO says that if you use a BAS to report GST collected and claim GST credits, you must keep records of all sales, tax invoices and other GST-related transactions. Provide:

  • Tax invoices you issued, or access to them in your invoicing software. A tax invoice for a taxable sale under A$1,000 needs seven details, including the seller’s ABN and the GST amount; sales of A$1,000 or more also need the buyer’s identity or ABN. You must give a customer a tax invoice within 28 days if they ask, unless the sale is A$82.50 or less including GST.
  • Point-of-sale, online store or payment platform reports. Daily summaries and settlement reports (for example from a card terminal, Shopify, Square or Stripe) that reconcile to what reached your bank.
  • Cash sales records. The ATO’s banking records page lists rolls of cash register tape and deposit slips among the records to keep, and says a daily reconciliation of cash sales should balance with the net cash sales banked.
  • Merchant facility statements for EFTPOS and credit card facilities.
  • Adjustments: credit notes, refunds, and price changes. The ATO says an adjustment, such as a price change on a sale or purchase or goods returned and a sale cancelled, is generally reported on the current BAS.

Step 4: purchase and expense records

  • Supplier tax invoices. The ATO says you must have a tax invoice before you can claim a GST credit, except for purchases of A$82.50 or less including GST. (ATO pages word the exact A$82.50 case differently, so if a purchase is right on the line, ask for the invoice.)
  • Receipts and statements for small purchases, including cash purchases. business.gov.au says you must keep records of all business expenses, including cash purchases.
  • Credit card statements and any card-paid subscriptions, with the invoices behind them.
  • Import documents. You do not need a tax invoice to claim GST credits on taxable imports, but the ATO says you must hold documents from the Department of Home Affairs showing the GST paid.
  • Foreign currency invoices. The ATO says to claim GST credits on the Australian dollar value.
  • Private or mixed-use items. The ATO says to claim GST credits only on the business portion, so tell your agent what was personal.
  • Supplier ABNs. If a supplier does not quote an ABN, the ATO says you generally need to withhold from the payment and pay that amount to the ATO, so flag any supplier without one.

Some purchases never carry GST credits. The ATO lists private expenses such as food or entertainment, GST-free items such as basic foods, and purchases without GST in the price such as bank fees and charges and stamp duty. Your agent will code these correctly, but the invoices still need to exist.

Step 5: bank, card and loan records

  • Bank statements for every business account, covering the whole period with no gaps.
  • Credit card statements, loan or lease agreements, and records of deposits and withdrawals, all of which the ATO lists as banking records to keep.
  • An explanation for anything unusual: transfers between accounts, owner contributions or drawings, and refunds.
  • Confirmation that every account is reconciled up to the end of the period. The ATO’s BAS tips say to reconcile sales with bank statements. If your Xero balance does not match the bank, see why a Xero balance can differ from the bank statement before you send anything.

Step 6: payroll and super records (if you have employees)

PAYG withholding is reported on your BAS, so your agent needs to see what you withheld. The ATO’s payroll record-keeping page says to keep:

  • Pay records for salaries, wages, bonuses, allowances and other payments, and Single Touch Payroll reports (STP does not change your record-keeping obligations or add new records).
  • Tax file number declarations and withholding declarations from your employees.
  • Super records: how you worked out the amount for each employee, and evidence of payment such as a bank statement, clearing house or SuperStream confirmation.

Payroll records need to be kept for five years.

Step 7: other documents, depending on your business

  • PAYG instalment notices or amounts you have been issued by the ATO.
  • Fuel tax credit records if you claim them. Business.gov.au lists these among the records you must keep.
  • Asset purchases and sales, with invoices and contracts, because GST on these is reported on the BAS and the ATO says you may need to repay GST credits for business assets you keep if your business changes or ceases.
  • Previous BAS and any ATO letters or notices you have received.

A simple timeline for a quarterly BAS

This is our suggested routine rather than an ATO requirement. The quarterly due dates (28 October, 28 February, 28 April and 28 July) are set by the ATO, and the ATO says BAS are usually available to an agent one week after they are generated, so leave room before your due date. Our guide on BAS due dates for 2026-27 explains the extra-time rules.

WhenWhat happens
Last week of the quarterChase missing invoices, update software, check bank feeds are working
First week after quarter endReconcile all accounts to the end of the quarter and send any unusual transaction questions to your agent
Second weekAgent reviews coding and GST, queries issues, prepares the BAS
Third weekYou approve the figures, and funds are set aside to pay
At least a few days before the due dateBAS lodged and payment made

Keep your records for five years

The ATO says you need to keep your GST records, banking records and employee payments records for five years from when you prepared or obtained them, or completed the transactions they relate to, whichever is later. business.gov.au adds that records need to be in English or easily translated, and stored so they cannot be changed or damaged. If you are behind with your records, our guide on catching up on overdue bookkeeping and BAS sets out the order to tackle them. And if you are still deciding what a BAS covers, read what a BAS is and whether you need to lodge one.

How we help

We give our BAS clients a simple checklist and a reminder before each due date, then do the preparation and lodgment for you. See our BAS agent services and bookkeeping services, or email info@guidancegrowth.com.au or use our get in touch page.

Frequently asked questions

What documents does a BAS agent need from me?

Authority to act (agent nomination), access to your accounting software and bank feeds, tax invoices for sales and purchases, bank and card statements, point-of-sale and cash sales records, payroll and super records if you have staff, and answers to questions about unusual transactions.

Do I need a receipt for every purchase?

You need a tax invoice to claim a GST credit unless the purchase is A$82.50 or less including GST. business.gov.au also says you must keep records of all business expenses, including cash purchases, so keep receipts regardless of amount.

Can I send photos of receipts?

Yes, generally. business.gov.au says the ATO accepts electronic images of paper records if they are a true and clear reproduction of the original and follow the record-keeping rules. Once saved, you do not need to keep the paper.

How long do I need to keep BAS records?

The ATO says to keep GST, banking and employee payment records for five years from when you prepared or obtained them or completed the transactions, whichever is later.

What if I am missing some invoices?

Tell your agent early. Request copies from suppliers. The ATO says you must have a tax invoice before claiming a GST credit, but you have four years to claim, so credits for late-arriving invoices can usually be claimed in a later BAS.

Do I need to authorise my BAS agent before they can lodge?

Yes. Entities with an ABN other than sole traders must nominate a new registered agent in Online services for business. The agent then has 28 days to add you as a client.

Sources and further reading

This article is general information, not personal advice. Rules and dates can change, so check ato.gov.au or acnc.gov.au for the latest, or speak to us about your situation.

Similar Posts