Your last 12 months were the best your business has ever had. The question is whether a lender will see it that way, or average it down with the slower year before. That's the core decision behind a 12 month bank statement loan versus a 24 month program, and picking the wrong window can leave real qualifying income on the table.
This guide explains how each option works, when one beats the other, and how to run the comparison on your own deposits before you apply.
Key takeaways
- Lenders average your eligible deposits over the window you choose, so the window directly affects your qualifying income.
- A 12-month window usually helps growing businesses; a 24-month window can help seasonal or uneven businesses.
- Lenders review trends either way, and a sharp decline can raise questions no matter which window you use.
- Some lenders treat 12-month programs a bit more conservatively, so options and pricing can differ between the two.
- The smart move is to calculate both before applying, which is easy if you download 24 months of statements up front.
How bank statement income averaging works
Every bank statement program follows the same basic recipe. The underwriter totals your eligible deposits over the window, removes anything that isn't business income, applies an expense adjustment for business accounts, and divides by the number of months.
That last step is where the window matters. Divide by 12 and you get the average of your most recent year. Divide by 24 and you get the average of two years, which blends your current performance with whatever happened before.
If you're new to the mechanics, our explainer on how bank statement loans work covers the full process, and our bank statement loan requirements guide lists everything else a lender will look at.
12 month bank statement loan: when it wins
A 12-month window is usually the better choice when:
- Your business is growing. If revenue climbed steadily, the recent year is likely your highest average.
- You recently raised prices or added a service line. The older year doesn't reflect your current earning power.
- Your business is newer. If you've only been operating for a bit over a year or two, a 12-month window may be the only practical option, depending on the lender.
- You had a one-time bad stretch more than a year ago, like a temporary closure or a lost contract, that you'd rather not average in.
It's also simpler. Fewer statements means fewer deposits to source and fewer pages for an underwriter to question.
The trade-offs
Some lenders view a 12-month window as a thinner track record. Depending on the lender, a 12-month program may come with somewhat tighter guidelines, fewer lender choices, or pricing that differs from the 24-month version. Many lenders treat them the same; some don't. That's one reason comparing multiple lenders helps.
24 month bank statement loan: when it wins
A 24-month window is often the stronger choice when:
- Your business is seasonal. Pool companies, landscapers, tax preparers, holiday retailers, and event businesses can have lopsided years. Two years smooths the curve.
- Your most recent year dipped, but the prior year was strong.
- You want to show stability. A longer track record can reassure an underwriter, especially on larger loan amounts.
- You want the widest lender selection. More lenders offer 24-month programs, and some reserve their most flexible guidelines for them.
The trade-off is that a strong recent year gets diluted if the older year was weaker.
Illustrative example: running both windows
Illustrative example — not an offer or a guarantee of qualifying income
Take a hypothetical HVAC contractor who owns 100% of the business and uses business bank statements. Assume, for illustration, that a lender applies a 50% expense factor to eligible deposits.
| Months 13–24 (older year) | Months 1–12 (recent year) | |
|---|---|---|
| Eligible deposits | $300,000 | $420,000 |
| After 50% expense factor | $150,000 | $210,000 |
12-month calculation: $210,000 ÷ 12 = $17,500 per month
24-month calculation: ($150,000 + $210,000) ÷ 24 = $360,000 ÷ 24 = $15,000 per month
For this growing business, the 12-month window shows $2,500 more per month in qualifying income. That difference can matter a lot when a lender is weighing your debt-to-income ratio.
Now flip it. Imagine a hypothetical pool-service company whose older year was $420,000 and recent year was $300,000 in eligible deposits. The 24-month window would show the higher average, but an underwriter will also notice the decline and may ask why. We'll come back to that.
Want both numbers before you commit? Our team can run your deposits through 12- and 24-month scenarios across multiple lenders. See if you qualify →
You can also get a rough feel for the numbers with our bank statement income calculator.
Seasonal businesses: smoothing the peaks and valleys
Seasonality isn't a red flag by itself. Underwriters see it constantly. What they want is a pattern that makes sense.
If your deposits spike every spring and drop every winter, a 24-month window will show two complete cycles. That tells the underwriter the slow months are normal, not a sign of trouble.
A 12-month window can still work for a seasonal business, as long as it captures one full cycle. The key is that the window is 12 consecutive months, so it naturally includes every season once.
Where seasonal owners get into trouble is the timing of the application. If you're mid-slow-season and your most recent statements look thin, an underwriter may ask for a letter explaining the pattern. Have that ready. A short, factual note like "Our revenue is concentrated in March through September; the attached statements show the same pattern in the prior year" goes a long way.
Growing vs declining revenue: what underwriters watch
Lenders don't just compute an average. They look at the trend inside the window.
Growing revenue
Steady growth is the easiest story to tell. Most lenders will take your average and move on. Occasionally, a very sharp jump in recent months prompts a question about whether it's sustainable, so be ready to explain a big new client or contract.
Declining revenue
A decline is more complicated. Many lenders compare the most recent months to the earlier part of the window. If deposits are falling meaningfully, the underwriter may:
- Use the lower recent figure instead of the full average
- Ask for a letter explaining the decline
- Request a year-to-date profit and loss statement
- Decline the file if the trend looks like it will continue
Choosing a 24-month window doesn't hide a decline. The underwriter can still see it. What helps is a clear, documented explanation, such as a one-time event, a planned shift in your business model, or a recovery already underway. Our guide on getting a mortgage with declining self-employed income covers how to handle this.
How the expense factor interacts with your window
The window determines how many months get averaged. The expense factor determines how much of each deposit counts. Both matter, and they work together.
Many lenders apply a standard expense factor to business statements, often somewhere around 50%, though it varies by lender and business type. Some allow a lower factor with a CPA or tax-preparer letter that supports your actual expenses. Personal statement programs typically treat deposits differently, since business expenses have already been paid before money reaches your personal account.
If your real expense ratio is low, as it often is for consultants, designers, and other service businesses, the expense factor may move your qualifying income more than the choice of window. Our deep dive on the bank statement loan expense factor explains your options.
How to choose: a simple decision process
- Download 24 consecutive months of statements for every account you might use.
- Total eligible deposits by month. Remove transfers between your own accounts, loan proceeds, refunds, and one-time non-business deposits.
- Compare your recent 12 months to the prior 12. Note whether you're growing, flat, or declining.
- Calculate both averages using a conservative expense factor.
- Look for seasonality and write a short explanation if your months vary a lot.
- Ask a broker to compare lenders for both windows, since guidelines and options differ.
If both windows produce similar income, the 24-month option may offer more lender choices. If the 12-month window shows meaningfully more, it may be worth any trade-offs.
Pricing and options: what differs in general terms
We can't quote rates here, and they change constantly anyway. In general terms, here's what to know:
- Non-QM pricing is typically higher than conventional, regardless of window.
- Some lenders price 12-month and 24-month programs the same; others view the 12-month version as slightly higher risk.
- Your credit, down payment, reserves, property type, and loan size usually affect pricing more than the window alone.
- Lender availability varies, and not every lender offers both windows in every state.
The only way to know the real difference for your file is to compare actual lender options side by side.
Frequently asked questions
Q: Is a 12 month bank statement loan harder to get than a 24 month one?
A: Not necessarily. Many lenders offer both with similar guidelines. Some apply slightly tighter requirements or offer fewer options for the 12-month version, so comparing lenders matters.
Q: Can I mix personal and business bank statements?
A: Some lenders allow it, but most want a consistent set of accounts across the window. If you switched from personal to business accounts partway through, explain it up front and expect the underwriter to review both.
Q: What if my business is seasonal and I'm applying in my slow season?
A: That's common and workable. Use a full 12- or 24-month window so every season is represented, and include a short letter explaining your seasonal pattern. Underwriters care more about the full-cycle average than one slow month.
Q: Will a 24-month window hide a decline in my income?
A: No. Underwriters look at trends within the window, and a meaningful decline can lead them to use the lower recent figure or ask for an explanation. Documenting the reason for the dip is far more effective than trying to average around it.
Q: Do I need a CPA for a 12 month bank statement loan?
A: Not always. Many lenders verify your business with a CPA or tax-preparer letter, but some accept a business license or Secretary of State filing. A CPA letter can also support a lower expense factor with some lenders.
Let's run both numbers for you
The difference between a 12- and 24-month window can be meaningful, and you shouldn't have to guess which one tells your story best.
Our team at Matador Lending compares bank statement programs across 150+ wholesale lenders. Send us your statements, and we'll show you how each window and each lender treats your deposits, with honest trade-offs included.
See if you qualify → — no credit pull to check your options. Prefer to talk? Call or text 713-366-4668.
This article is general education, not tax, legal, or financial advice, and not a commitment to lend. Loan programs, guidelines, and availability vary by lender and state and change without notice. Non-QM loans are subject to credit approval, income and asset verification, and appraisal. Talk with your CPA about tax questions. Small Business Mortgages is a marketing brand of Matador Lending, NMLS #2072896. Equal Housing Opportunity.