Does One Bad Year Hurt a Bank Statement Loan More Than Several?

The Quick Read: Usually not: one weak year gets averaged, explained, or set aside, while several weak years form a downward trend that underwriters read as a direction rather than just an average, and a 12-month or 24-month window can soften the average without hiding the slope.

• A single down year is survivable when deposits have stabilized and the file has clean sourcing, solid credit, and reserves.
• Several weak years, or a steady slide, shrink qualifying income and raise doubt that income is current or likely to continue.
• Where the weak period sits matters. Recent weakness hurts more than old weakness.
• The window you pick changes the average, not the direction of the trend.
• A rental that covers its own payment may make a debt-service-coverage (DSCR) loan a better fit than a deposit-based file, subject to lender guidelines.

How a Bank Statement Loan Reads a Bad Year

A bank statement loan is reviewed on documented income under the applicable program, subject to lender guidelines. The lender looks at deposits, not the taxable income on your returns. That distinction is why a bad tax year and a bad deposit year are two different problems.

A tax-return “down year” often comes from write-offs. Depreciation, equipment purchases, and business expenses can shrink taxable income while cash keeps flowing through the account. Deposits don’t carry that distortion, so a deduction-driven dip usually doesn’t follow you into a bank statement file. Tax treatment varies; consult a qualified tax professional before relying on any deduction.

A real drop in deposits is different. It lowers the average, and the average is the number the file lives on.

Across Lendmire’s wholesale network, the common baseline is 12 months of personal or business statements. Some programs allow a longer 24-month window, but that depends on the individual program. Business accounts usually get an expense factor applied to deposits, set by the lender rather than the borrower. Some programs accept an accountant-prepared expense ratio instead, which can change the result. Never assume a specific factor before a lender has reviewed the file.

One Bad Year, Three Placements

The same weak year does different damage depending on where it falls in the statement window.

The bad year is the older one. A 12-month window skips it entirely. A 24-month window blends it in and pulls the average down. If income has recovered, the shorter window usually tells the better story.

The bad year is the most recent one. This is the hardest case. A 24-month window can soften the average by mixing in a stronger prior year. But the slope still shows, and a lender may anchor on the latest 12 months anyway.

One weak quarter inside a 12-month window. There are fewer months to dilute it, so each weak month carries more weight. Underwriters will usually want a written explanation of what happened and proof that deposits have returned to normal.

Seasonal or lumpy income adds a twist. A longer window can be fairer for a business with a slow season. A 12-month window that happens to capture the peak season can overstate typical income, and an underwriter may notice.

Why Several Weak Years Cost More Than One

Averaging helps only while most of the window is strong. Once most of the months are weak, there is nothing left to dilute them.

More important, a pattern changes what the underwriter is asking. With one weak year, the question is whether something unusual happened. With several, the question becomes whether the business is shrinking. That second question is much harder to answer with a letter.

The four illustrative patterns below show how the same borrower type can read very differently. They are simplified examples, not program rules.

The pattern that does the most damage is the slide. A lender sees the same low average as the flat weak borrower, but with no floor under it.

12 Months or 24 Months When Income Has Dipped

Choosing a window feels like a strategy. It is closer to a math choice, and the direction of the trend still shows under either one.

Run both calculations before you apply, if the program offers both. The gap between the two averages tells you how much a lender’s choice of window could move your qualifying income.

A Worked Example With Indexed Numbers

Dollar amounts vary too much by business to be useful here, so this example uses an index. These are modeled assumptions, not market data.

Say average monthly deposits in the older year index at 100. In the recent year they fall to 70 and stay there.

• A 12-month window uses 70.
• A 24-month window averages the two years to 85.

The longer window looks about 21% better than the shorter one (85 against 70). But the recent months still sit at 70, and the slope is the first thing an underwriter will notice.

Now take a steady slide: 100, then 85, then 70 across three years. A 24-month window covering the last two years averages about 77.5. That still looks better than the 70 sitting in the latest months, but a lender can see where it’s heading.

Lower qualifying income also flows straight into the debt-to-income test. If qualifying income drops 30% and the new payment stays the same, a file sitting at 30% debt-to-income lands near 43%. The same file, with a smaller income number, now looks much heavier. On a business account, the expense factor makes this worse, because it shaves a percentage off an already lower deposit base.

What Lenders Must Do With a Falling Trend

Non-QM loans still have to rest on a good-faith look at ability to repay. The CFPB’s ability-to-repay rule treats that as a judgment based on the creditor’s own underwriting standards and how they apply to the facts of the loan. The rule doesn’t tell a lender how to treat a down year. Each lender’s guidelines decide that.

The Federal Register notice adds that the determination must rest on verified, documented information and reasonably reliable third-party records. It sets no numeric debt-to-income limit for non-QM loans. Nolo’s overview confirms lenders weigh income, employment, and credit history together.

The practical result is that income has to look current and likely to continue. A falling trend makes that harder to show, which is why direction matters beyond the arithmetic.

Seasonal, One-Time, or Structural?

Lenders object to unexplained variability more than variability itself. Before you apply, sort your dip into one of three buckets.

• Seasonal: Weak months repeat at the same time each year. A 24-month window shows the pattern and helps the story.
• One-time: A lost client, a delayed project, or a medical leave with a clear start and end. A specific letter and recovery in recent months can carry this one.
• Structural: Fewer clients, a shrinking market, or a business that has changed shape. This is the bucket where several weak years do the most harm.

If you can’t tell which bucket you’re in, an underwriter probably can’t either. That is a sign the file needs more documentation or more time.

How to Strengthen the File

1. Run both windows. Know the 12-month and 24-month numbers before a lender does.

2. Write a specific explanation letter. Name the cause, the dates, and what changed. A generic letter doesn’t help.

3. Show recent months. Recent statements that sit above the weak stretch are the best evidence that the dip has ended.

4. Keep funds separate. Mixing personal and business deposits muddies the average and invites sourcing questions.

5. Document one-time deposits. Transfers between your own accounts, loan proceeds, refunds, and windfalls usually come out of income, so flag them first.

6. Prepare a CPA letter or profit-and-loss statement. Some programs allow an accountant-prepared expense ratio in place of the default factor.

7. Wait when waiting is cheap. A few more clean months can lift the recent-window average more than any letter can.

Compensating strength matters too. Stronger credit, healthy reserves, and lower leverage can offset a thinner income figure. Reserves commonly run around six months of the housing payment on bank statement files.

Lendmire’s piece How to Qualify for a Bank Statement Loan With One Declining Deposit Year goes deeper on the single-dip case.

Where the Leverage Lands

Leverage depends on how the property is used. On a primary residence, select lenders in the network allow up to 90% LTV on a purchase or rate-and-term refinance, with stronger files earning the top of that range. On an owner-occupied cash-out (primary residence or second home), the ceiling is up to 80% LTV with a fixed expense ratio, or 75% with an accountant-prepared ratio. On an investment-property cash-out, leverage tops out around 75% LTV. Investment purchases on bank statement documentation vary by lender.

Loan sizes generally run from $125,000 to $3,500,000. All of these are subject to lender guidelines, credit approval, and property review.

A weaker income year doesn’t change those ceilings on paper. It does make the top of the range harder to reach, because lenders reserve their highest leverage for the cleanest files.

When a Bank Statement Loan Isn’t the Best Fit

If your personal deposits are down but the rental pencils, DSCR may fit better. These loans are designed for non-owner-occupied investment properties, and they are reviewed on a business-purpose basis. They qualify primarily on property-level rental income covering the payment, subject to lender guidelines. Your own income year matters much less.

It isn’t automatically better. If the rent is thin against the full monthly obligation, a strong deposit file can be the better path. Lendmire’s piece DSCR Loan Vs Bank Statement Loan For Investors lays out when each one tends to win. For the wider picture, see the complete DSCR loans guide.

Note that bank statement files still test your other debts, so a growing rental portfolio can compound a down-income year. A DSCR file avoids that stacking effect, though the subject property’s rent still has to carry it.

Key Terms Defined

Lookback window: The number of months of bank statements the lender averages to find your income.

Deposit averaging: Adding eligible deposits over the window and dividing by the number of months.

Expense factor: A percentage a lender subtracts from business deposits to account for the cost of running the business.

Trend review: The underwriter’s check of whether recent months are rising, flat, or falling against the average.

Letter of explanation: A written account of why income dipped, with dates and specifics.

What to Ask a Loan Officer

• Which window does this program use, and is a longer one available?
• How is the expense factor set, and can an accountant-prepared ratio replace it?
• Do you anchor on the latest 12 months if the trend is down?
• Which deposits will you exclude?
• How would my leverage change at my credit score and loan size?

Lendmire is a broker, not a lender, and nothing here is a commitment to lend. An editable calculator on the site can give an illustrative estimate before you talk to anyone.

Investors who find the right window and the right program for their pattern tend to discover that a down year is rarely the real obstacle, because the trend behind it is.

About Lendmire

Lendmire is a DSCR-focused mortgage brokerage, NMLS# 2371349, placing investor loans across 41 markets, including Washington, D.C. DSCR eligibility is generally reviewed by the lender around a property’s rental income rather than personal income documentation, which fits LLC-held rentals, self-employed investors, and portfolios scaling past conventional financed-property limits. Scotsman Guide named Lendmire a Top Mortgage Workplace in both 2025 and 2026.

References

1. CFPB Regulation Z § 1026.43

2. Federal Register, Ability-to-Repay and Qualified Mortgage Standards

3. Nolo, New Mortgage Rules: Ability to Pay