To prove income for a self-employed mortgage, you give the lender your SA302 tax calculations and matching tax year overviews from HMRC, usually covering the last two to three years. Sole traders and partners use the profit figures from their Self Assessment returns; company directors usually combine salary and dividends, or sometimes retained profit. Most lenders want a consistent, evidenced track record before they will lend.
If your tax returns are filed correctly and on time, the paperwork is straightforward. The problems start when returns are late, profits are erratic, or your accounts and your tax return do not tell the same story.
What Documents Do Mortgage Lenders Ask For?
Lenders want HMRC-issued evidence that matches your declared income. The two core documents are the SA302 and the tax year overview, and you almost always need both, because lenders cross-check one against the other.
| Document | What it shows | Where to get it |
|---|---|---|
| SA302 tax calculation | A breakdown of your income and tax for a given year | HMRC online account or your accountant's software |
| Tax year overview | Confirms the tax due and paid, proving the SA302 is genuine | HMRC online account |
| Finalised accounts | Profit and loss for your business (often needed for limited companies) | Your accountant |
| Business bank statements | Typically the last 3-6 months | Your bank |
You usually provide two or three years of SA302s and overviews. Some lenders accept one year if the rest of your profile is strong.
How to Get Your SA302 and Tax Year Overview
You can download both from your HMRC online account once your Self Assessment return is submitted. Note that you cannot print them until 72 hours after filing, so do not leave it to the last minute before a mortgage deadline.
Log in to your HMRC account, go to Self Assessment, then More details about your Self Assessment returns and payments, and select the relevant tax years. If an accountant files for you using commercial software, they can produce an equivalent SA302 directly, and most lenders on HMRC's accepted-lender list take these.
If your Self Assessment is filed accurately and early, your evidence is ready when the lender asks.
How Do Lenders Calculate Self-Employed Income?
This depends on your business structure.
Sole Traders and Partners
Lenders use your net profit (sole trader) or your share of partnership profit, not your turnover. Most average the figure across two or three years; if profits are falling, many use the lower or most recent year to be cautious.
Limited Company Directors
This is where people get caught out. If you take a small salary and leave profit in the company, your SA302 may show a low income even though the business is doing well.
Lenders typically assess directors in one of two ways:
- Salary and dividends, the income you actually drew, shown on your Self Assessment.
- Salary and share of net (retained) profit, a growing number of lenders use this, which can sharply increase your borrowing power if you have retained earnings.
Remember that the dividend allowance is just £500 for 2026/27, so dividends above that are taxed. Drawing more to boost your mortgage figure carries a real tax cost, so model it before you act.
How Much Can You Borrow?
Most lenders offer 4 to 4.5 times your assessable annual income, and some go higher for strong applicants. So if your averaged self-employed profit is £45,000, you might borrow roughly £180,000 to £202,500, subject to affordability and deposit.
Your assessable income sits within the 2026/27 bands:
| Band | Taxable income | Rate |
|---|---|---|
| Personal allowance | Up to £12,570 | 0% |
| Basic rate | £12,571 - £50,270 | 20% |
| Higher rate | £50,271 - £125,140 | 40% |
| Additional rate | Over £125,140 | 45% |
Here lies a common tension: aggressive expense claims lower your tax bill but also lower the profit a lender will recognise. There is a genuine trade-off between paying less tax now and borrowing more later.
Can You Get a Mortgage With Only One Year of Accounts?
Yes, but your options narrow. A smaller pool of lenders accept a single year's SA302, and they will usually want a larger deposit, a clean credit file, and evidence that trade is stable or rising. A specialist broker matters far more here than for a two- or three-year applicant.
Common Mistakes That Sink Applications
- Filing late. A missed deadline means no SA302 for that year, and a £100 penalty on your record.
- Mismatched figures. Your accounts and tax return must agree. If your accountant's profit and your SA302 differ, expect questions.
- Claiming the trading allowance and then needing the income. The £1,000 trading allowance is handy for tiny side income, but if you use it instead of declaring real profit, you have understated provable income.
- Forgetting capital allowances. Heavy use of the £1,000,000 Annual Investment Allowance in one year can crater that year's profit, and the figure a lender sees.
Getting your numbers presented correctly, and consistently across documents, is half the battle. Our FAQ page covers more on filing and timing.
Frequently Asked Questions
How Many Years of Accounts Do I Need for a Self-Employed Mortgage?
Most lenders want two to three years of SA302s and tax year overviews. Some accept one year with a stronger deposit and clean credit, but your choice of lender will be smaller and rates may be higher.
Does an SA302 Alone Prove My Income?
No. Lenders pair the SA302 with the matching tax year overview, which confirms the tax was actually declared and paid. The two documents together prove the figures are genuine, not just a printout.
Can I Use Retained Profit in My Limited Company to Borrow More?
Some lenders assess directors on salary plus their share of net profit rather than just salary and dividends. This can significantly boost borrowing power if you have left profit in the company, but not every lender offers it, so you will usually need a specialist or broker.
Will Claiming Lots of Expenses Hurt My Mortgage Chances?
It can. Expenses and allowances reduce your taxable profit, which is the figure lenders assess. Cutting your tax bill aggressively in the years before applying also cuts how much you can borrow, so plan the timing.
Proving self-employed income comes down to clean, consistent, on-time tax returns; the rest is presentation. If you want your SA302s mortgage-ready and your profit positioned correctly across every document, get in touch with Zmartly and we will make sure your numbers stand up when the lender looks.
