Chapter 6

BAS: what is it and how to lodge it

GST-registered businesses declare how much they’ve collected and paid by completing a business activity statement (BAS).

A BAS form being scanned onto a laptop

What is a BAS?

A BAS is a form that you fill out between one and twelve times a year, depending on your business size. The ATO uses the information on your BAS to work out your GST refund or bill. It’s also used for business income tax (if you’re in the pay-as-you-go system), employee income tax, fringe benefits tax, luxury car tax, wine equalisation tax, and fuel tax credits.

Information you will need

You’ll need a record of how much GST you collected on sales, and how much was paid on purchases. You won’t need to submit tax invoices when you lodge your BAS, but you will need to have them on hand. The ATO may ask to see them later.

Because your BAS may also be used for other tax reasons, you will probably need to provide extra information about your business, its income, and any employees. Learn more on the ATO page about business activity statements.

How to lodge a BAS

You can lodge your BAS online:

What are BAS due dates?

How often you complete a BAS – and when you must submit it – depends on how much business you’re doing. And that’s measured by your annual turnover.

More than $20 million annual turnover

Lodge: Monthly.

Deadlines: You must submit a BAS within 21 days of the month closing.

Less than $20 million annual turnover

Lodge: Quarterly.


  • Quarter 1 (July-September) BAS is due on 28 October.
  • Quarter 2 (October-December) is due on 28 February.
  • Quarter 3 (January-March) is due on 28 April.
  • Quarter 4 (April-June) is due on 28 July.

If your turnover is less than $10 million, you may be able to lodge annually – but you’re still required to pay a quarterly instalment of the GST you owe.

Less than $75,000 annual turnover (or $150,000 for non-profits)

Lodge: Annually.

Deadline: Submit with income tax return.

If you miss your BAS due date

You may be penalised by the ATO if you blow your BAS deadline without a good reason. Here’s how they calculate the size of the fine.

GST payment

If your BAS says that you owe GST, then you are generally required to make that payment on the same day. You can pay online, by mail, or in person at Australia Post.

If you can’t afford to pay the GST you owe, you may still be able to avoid a fine by lodging your BAS on time, then working out a payment plan with the ATO.

Getting a GST refund

If you paid more GST than you collected, the ATO will owe you a refund. It will be paid directly into your nominated bank account.


Xero does not provide accounting, tax, business or legal advice. This guide has been provided for information purposes only. You should consult your own professional advisors for advice directly relating to your business or before taking action in relation to any of the content provided.

GST and BAS Guide For Business

Making a start with GST and BAS? Don’t worry. It’s a little extra admin, but this guide will help you get sorted.

  1. What is GST?

    You’ve probably heard about GST – it stands for goods and services tax and is added to most prices in Australia.

  2. Registering for GST

    Find out if your business needs to register for GST. If so, learn how to do it and find out what happens next.

  3. Calculating GST and issuing tax invoices

    If you’re a GST-registered business you must add GST to your prices. You also need to issue GST invoices. Find out how.

  4. Claiming back GST (and input tax credits)

    GST-registered businesses can claim back the GST they pay on business expenses. Let’s learn how to claim it.

  5. Working out your GST refund or payment

    Working out GST is simple maths. Keeping track of all your transactions is the tricky part. Let’s learn the process.

  6. What is BAS and how to lodge it

    GST-registered businesses declare how much they’ve collected and paid by completing a business activity statement (BAS).

  7. Tools and guides for your business

    Now you know the ins and outs of GST and BAS, but it can be tough to manage it all. Xero’s got the resources to help.

Download the GST Guide for Business

Get your GST sorted. Fill out the form to receive this guide as a PDF.

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