If you run a business and lodge BAS with the ATO, your Business Activity Statements may be the most powerful tool you have when applying for a home loan. But the way lenders interpret those statements varies significantly - and the calculation method they use can mean a six-figure difference in your borrowing capacity.
By Jason Given - August 2026 - 6 min read
A BAS statement home loan is a home loan where the lender uses your Business Activity Statements as the primary evidence of income, instead of tax returns. BAS statements are lodged quarterly with the ATO and show your GST turnover, making them a reliable indicator of business revenue.
This is the most common form of alt doc or low doc lending in Australia. Because BAS is lodged with the ATO and can be independently verified, lenders treat it as a strong form of income evidence - stronger than bank statements or accountant letters in most cases.
For self-employed borrowers whose tax returns understate their true earning capacity - whether through legitimate deductions, business reinvestment, or timing issues with their accountant - BAS verification provides a way to demonstrate actual business revenue to a lender.
This is where the detail matters. Different lenders use different methods to convert your GST turnover into an assessable income figure, and the method they choose can dramatically affect how much you can borrow.
The most common approaches include:
The calculation method can mean a difference of tens of thousands of dollars in assessed income from the same BAS statements. This is why lender selection is critical for BAS-based applications.
Consider a business owner whose BAS shows $300,000 in annual GST turnover. Here is how three different lenders might assess that income:
The $30,000 difference between Lender A and Lender B alone could mean $100,000 or more difference in borrowing capacity. For a professional services business, Lender C's industry-specific margin could unlock significantly more again. This is why choosing the right lender for your specific business type is not optional - it is the single biggest lever in a BAS application.
Most lenders require the last 4 consecutive quarterly BAS statements, covering 12 months of business activity. Some lenders will accept the last 2 quarters if the business is well-established with a long ABN history.
There are a few important requirements to be aware of:
BAS verification works best for businesses with consistent turnover. Tradies, consultants, healthcare providers, and professional services firms are all well-suited to this approach because their revenue tends to be steady and predictable.
Businesses with high margins benefit the most from BAS lending. If your actual profit margin is 65% but the lender only applies 50%, you are leaving money on the table. Conversely, if your margins are thin (say 25% in a product-based business), a lender applying 50% will overstate your income - which sounds good until the repayments become unaffordable.
Seasonal businesses may need to show the full 12 months of BAS to smooth out peaks and troughs. A landscaper who does 60% of their revenue between September and March, for example, would not want a lender using only the most recent quarter if that quarter falls in winter.
When it comes to alt doc income verification, not all evidence is treated equally by lenders. Here is how the three main forms compare:
BAS statements are generally the strongest form of alt doc evidence. Because they are lodged with the ATO and tied to your GST obligations, most lenders prefer them over other forms. They offer the widest range of lender options and typically the most competitive rates within the alt doc space.
Bank statements are useful when BAS is not available (for example, if you are not registered for GST) or when your cash flow is stronger than your BAS suggests. Some lenders will accept 3-6 months of business bank statements showing regular income deposits.
Accountant letters (also called accountant declarations) can supplement a BAS or bank statement application, but they rarely stand alone. Most lenders want at least one other form of evidence alongside the accountant's declaration. Some lenders accept a combination of all three.
Yes, BAS-based lending requires GST registration. If your business turnover is below the $75,000 GST threshold and you are not registered, BAS verification is not available. You would need to use bank statement or accountant verification instead.
Yes, most lenders accept BAS from companies, trusts and partnerships as well as sole traders. The entity structure may affect how income is attributed to you personally - for example, if you earn income through a trust, the lender will need to understand how distributions flow to you as the borrower.
Some lenders will use the average of all 4 quarters, which smooths out a decline. Others use the most recent quarter annualised, which could work against you if the latest quarter is the weakest. Lendology identifies which assessment method works best for your BAS trend - in some cases, a lender that averages will give you a better result than one that focuses on the most recent quarter.
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