Submitting your BAS form is a legal requirement for most businesses. It’s either a monthly, quarterly or annual financial task that, as a business owner, you know is on the cards. Too often, however, it comes as a surprise. And that’s not good for your business, or your stress levels.

Your BAS shouldn’t be a moment of reckoning, a scramble to work out what your liabilities are, and a search to see if you have the cash on hand to meet them.

If you make it a regular part of your financial procedures, it becomes an opportunity. Not only will you meet your legal obligations, but your BAS can be a useful tool to help manage cash flow and provide insights to guide future planning.

Who needs to submit a BAS?

A BAS (Business Activity Statement) is how you declare to the Australian Taxation Office your business’s GST collected and paid, PAYG withholding, PAYG instalments, and any other business taxes you need to pay.

You need to submit a BAS if your business has an annual GST turnover (income excluding GST) of more than $75,000, or $150,000 or more for non-profit organisations. Businesses with a turnover below the GST threshold don’t have to register for GST. However, many choose to register voluntarily to claim credits or appear more established.

In addition, any businesses that withhold tax from employee wages, pay PAYG instalments, or have other reportable tax obligations (fringe benefits tax, luxury car tax, wine equalisation tax, or fuel tax credits) are also required to lodge a BAS.

How to lodge your BAS: step-by-step

Here’s a simple step-by-step guide to lodging your BAS with the ATO. Once you’ve done your first BAS, it will follow the same process each time you submit.

1. Prepare your records

Before you even open your BAS, you need to make sure your financial records are complete and accurate.

We’re talking sales invoices and receipts for the period. Purchase invoices, especially tax invoices for GST claims. Bank and credit card statements. Payroll records (if you employ people). Any superannuation and PAYG withholding records.

Lots of businesses have an online system to store and manage this data. Purpose-built accounting software allows you to add attachments (invoices, GST receipts, etc) and will also do the maths and provide you with reports.

2. Calculate your figures

Once your records are in order, you can calculate the figures that will appear on your BAS (some software will do this automatically). Remember that, in your BAS, you are reporting totals, not each transaction.

As mentioned, the figures you’ll need to report are your GST on sales, GST on purchases, PAYG withholding, and PAYG instalments. You’ll also want to reconcile your bank accounts, making sure that the transactions in your system line up with your bank and/or credit card statements. If the numbers don’t match, you’ll need to comb through your records for missing transactions, input errors or duplicates.

3. Lodge your BAS

Once you’ve got all the numbers reconciled and clear, you can lodge your BAS via the method that best suits your business.

The most common options are:

• Online: Through the ATO’s services for business portal (the ATO reports that online BAS lodgement is the most common method).
• Accounting software: From SBR accounting or payroll software, which will submit your BAS directly to the ATO.
• Through a registered tax or BAS agent: Such as Visory, who can complete and lodge a BAS on your behalf.
• By mail: Using the paper BAS form issued by the ATO.
• By phone: Available for nil BAS lodgements only.

Remember: even if you have nothing to report, you still need to lodge your BAS as nil by the due date.

4. Pay any amount owed or receive a refund

When you’ve finished entering all the numbers in your BAS form (or through your software or agent), the form calculates whether you owe any tax or are due for a refund.

If you owe money, payment is usually due on the same date as lodgement. You can pay via online banking, BPAY, credit card (although there is typically an extra fee for this method), or other approved options. If you’re due for a refund, it will typically be processed automatically once the BAS is lodged. While refund timing can vary, electronic lodgement generally leads to a faster turnaround.

Remember: If you can’t lodge or pay on time, contact the ATO straight away. They may be able to provide you with options to defer lodgement, set up a payment plan, or reduce penalties. However, none of this is guaranteed, so we recommend contacting the ATO directly for advice.

Key dates for BAS lodgement

How often you lodge your BAS depends on how your business is registered with the ATO. They will decide based on your GST and PAYG obligations whether you will need to lodge monthly, quarterly, or annually.

Here’s an outline of what each of the reporting periods looks like with their key dates.

BAS reporting periods

*Data taken directly from the ATO’s website as of March 2026. Please visit their official website for the most up-to-date information.

Remember: if a due date happens to fall on a weekend or public holiday, the date will move to the next business day.

5 common BAS mistakes, and how to avoid them

Often, submitting your BAS form isn’t the hard part. The tricky bit is ensuring all your financial records are accurate beforehand.

Here are some common mistakes businesses make, and simple ways to prevent them.

1. You claim GST you’re not entitled to

Not all expenses include claimable GST. For example, input-taxed items, private expenses and invoices without valid tax details. Only claim GST for valid tax invoices, and when the expense is business-related. Not sure? Don’t include it.

2. You mix up cash and accrual accounting

Report income and expenses in the wrong period, and you’ll distort your BAS figures, especially if you invoice ahead or pay your bills late. Whichever accounting method your business uses, stick to it consistently.

3. You don’t reconcile your accounts

Unreconciled bank accounts can lead to missing income, duplicated expenses or incorrect totals. Cross-check all bank and credit card accounts so that mistakes don’t flow through to your GST and PAYG.

4. You incorrectly code expenses

This could include coding non-GST or private costs as claimable business expenses, or forgetting to adjust for refunds. Always double-check your categories to make sure everything’s where it should be. Any split, refunded or unusual transactions must be corrected before lodging the BAS.

5. You forget PAYG withholding

This is easy to miss if you haven’t finalised your payroll or your reports aren’t up to date when the BAS period comes around. Always complete your payroll and confirm your withholding totals before completing your form.

Taking your BAS from obligation to insights

Treating your BAS as a compliance task is important. After all, no one wants to fall foul of the ATO. However, your BAS can be so much more.

If you’re currently lodging your BAS and hoping it’s accurate, you’re missing the opportunity to get out in front of your financials and make the most of the insights that the BAS can provide.

Your BAS shouldn’t be divorced from your other processes or separate from the day-to-day running of your business. That approach leads to pressure at lodgement time and a missed opportunity.

If the only time you review your records is at the very end of the BAS period, you might not notice important signals that your finances are giving you, before they noticeably impact business performance. Things like revenue shifts, rising costs and changing tax liabilities.

When your bookkeeping is accurate, up-to-date and reviewed regularly, BAS becomes less of a compliance task and more of a marker along your financial journey. Your tax obligations are no longer things that rear their head sporadically, but become something integral to your planning and much more easily prepared for.

The good news is that this integrated approach is what Visory excels in. As your financial performance partner, we can go beyond helping you prepare and lodge your BAS. We can help you understand what it’s telling you. Connect with an expert to find out more.

5 things your BAS can tell you beyond compliance

If you treat your BAS as more than a box-ticking exercise, you can start unearthing some valuable signals regarding the health of your business. Here are five insights to look out for.

1. Whether revenue is genuinely growing

Trace your BAS figures across several periods and you’ll see whether your growth is consistent, seasonal or beginning to plateau. This is a simple check to see if your top line is moving in the right direction or drifting off course.

2. Whether you’re controlling costs

If your GST credits are rising faster than the GST being collected, rising costs might be eating into your margins.

3. Whether you have good cash flow habits

Healthy businesses have forward visibility on what they will owe, with cash set aside in preparation for these expenses. If you can meet your BAS obligations without scrambling for the cash at the last minute, that’s a good sign your cash flow management processes are in decent shape. If it’s always a stretch to find the funds, you might need to build stronger cash reserves.

4. Whether there are timing pressure points

You can use your BAS to identify any mismatches between when money comes in and when it needs to go out. For example, you might owe GST on income you haven’t received yet, or when you need to pay expenses ahead of receiving revenue. These sorts of discrepancies can feed into cash flow volatility, as well as cause unnecessary stress.

5. How stable your business really is

If you spot big swings in your BAS liabilities from one period to the next, that may be a sign of underlying volatility, be it seasonal revenue dips or irregular spending. Understand these fluctuations, and you gain more control of your finances and can more easily plan for the future.

The importance of cash flow for compliance, and peace of mind

One of the most practical benefits of moving beyond a BAS-only mindset is that you can make sure you have the requisite cash on hand when payments are due. BAS deadlines can bring pressure. Not only do you need to do all the calculations to confirm your liabilities, but you also need to find the funds at the right time.

A more unified approach is to separate and manage that cash progressively. This can be as simple as regularly transferring a portion of revenue into a dedicated account, based on expected GST and withholding obligations. By incorporating BAS into your regular record-keeping activities, you can estimate these amounts with reasonable confidence and adjust your cash flow as needed across the quarter.

Preparing for BAS in smaller, manageable steps is much easier on both the cash flow situation and your stress levels than having to generate a large, lump-sum payment. It also creates a clearer picture of the cash you have available for other business activities.

Managing cash flow around BAS effectively is not just a safeguard. It is also a reflection of stronger financial control.

Take full control of your BAS with Visory

When you work with Visory, you gain a business performance partner. We can take care of the details of your BAS, of course, but we’ll also give you insights that can enable you to fully understand your financial situation, identify opportunities, and make confident calls on when and how to invest, hire or grow.

Book a no-obligation online meeting with one of our experts to discover how we can turn your BAS into something so much more than a compliance requirement.

FAQs

What happens if I lodge my BAS late?

If you lodge your BAS late, the ATO may apply penalties or interest. That said, how this is handled does depend on your history and whether you are proactive. For example, if you know you’re going to be late or you’ve missed the deadline, contact the ATO early to discuss your options.

How does the ATO check what you submit in your BAS?

The ATO doesn’t manually review every BAS as it’s lodged. Instead, they use automated checks and data matching to flag anything that looks unusual. If something seems odd, they may contact you after your submission and ask for records to support what you have reported.

What happens if I make a mistake in my BAS form?

The ATO generally understands that mistakes happen, but it’s important that you come forward and fix them. Depending on the level of the error, you may be able to make a resubmission or simply add the missed transaction to your next period. If your original BAS was correct but something changed later (like a refund), you can report this as an adjustment in your next period. You can learn more about fixing mistakes directly on the ATO’s website.

What’s the value in using a BAS agent or accountant?

While you’re not required to use a BAS agent or accountant to lodge your BAS, for many businesses that support can be invaluable. Working with a performance partner like Visory, you’ll not only be confident that everything has been done properly and you’re compliant with the rules, but you can also gain financial insights from the BAS that can feed into your long-term growth strategy. Connect with an expert to find out more.