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Documentation Guide

SA302 Guide: Everything You Need to Know

Understanding SA302 tax calculations — what they are, how to get them, what they show, and why mortgage lenders need them.

Updated January 20268 min read

What is an SA302?

An SA302 is a document from HMRC that shows your taxable income for a specific tax year. It's essentially a summary of your self-assessment tax return, confirming the income figures you declared and what HMRC has on record.

Why lenders want it

The SA302 is proof of your declared income. Unlike payslips (which employers could theoretically fabricate), SA302s come from HMRC and represent what you've officially declared to the tax authorities. This gives lenders confidence in your income figures.

Official Name

The SA302 is officially called a "Tax Calculation" by HMRC. You may also hear it referred to as:

  • SA302 Tax Calculation
  • Tax Computation
  • HMRC Tax Calculation
  • Self-Assessment Tax Calculation

What It Shows

Your SA302 contains key information about your income for a tax year (6 April to 5 April the following year):

SA302 — Tax Calculation

Tax year2024-25 (6 April 2024 to 5 April 2025)
Self-employment income£65,000
Employment income (if any)£0
Dividend income£35,000
Property income (if any)£0
Total income£100,000
Tax due£27,432

Key Fields for Mortgages

Self-Employment Profit

Your net profit from self-employment after deducting allowable expenses. This is the primary figure for sole traders.

Dividend Income

Dividends received from your company (if Ltd director). Key for salary+dividends calculations.

Employment Income

Any PAYE employment alongside self-employment. Shows total picture for mixed income applicants.

Total Taxable Income

Combined total of all income sources before tax. Used for overall affordability assessment.

How to Get Your SA302

Option 1: HMRC Online (Fastest)

Recommended
  1. 1. Log into your HMRC Personal Tax Account (Government Gateway)
  2. 2. Go to "Self Assessment" section
  3. 3. Select "More Self Assessment details"
  4. 4. Choose "Get your SA302 tax calculation"
  5. 5. Select the tax year you need
  6. 6. Print or save as PDF

Time: Immediate (if you've filed your tax return)

Option 2: Request by Phone

Call HMRC Self Assessment helpline: 0300 200 3310

They'll post your SA302 to your registered address. Allow 7-10 working days.

Time: 7-10 working days

Option 3: Via Your Accountant

Your accountant can produce a tax calculation from their software. This shows the same information and is accepted by many lenders.

They may also be able to access the official HMRC version through their agent services.

Time: Usually 1-3 days

Tax return must be filed first

You can only get an SA302 for tax years where you've already filed your return. If you haven't filed for the latest tax year, you'll only have access to older years' SA302s.

Tax Year Overview

Most lenders also require a Tax Year Overview alongside your SA302. This is a separate document that confirms your tax position with HMRC.

What's the Difference?

SA302 (Tax Calculation)

  • • Shows income breakdown
  • • Details of each income source
  • • How tax was calculated
  • • Based on your tax return

Tax Year Overview

  • • Confirms return was received
  • • Shows tax owed/refunded
  • • Payment status
  • • HMRC's official record

How to Get Your Tax Year Overview

Same process as SA302 — through your HMRC online account. In the Self Assessment section, select "View your Tax Year Overview" for the relevant year.

Get both at once

When downloading documents for your mortgage, get both the SA302 and Tax Year Overview for each year in one session. Lenders almost always require both.

Lender Requirements

How Many Years?

1

year

Minimum (some specialists)

2

years

Most common requirement

3

years

Some cautious lenders

Which Tax Years?

Lenders want the most recent complete tax years. For applications in January 2026:

  • Latest2024-25 (April 2024 - April 2025)
  • Previous2023-24 (April 2023 - April 2024)
  • If needed2022-23 (April 2022 - April 2023)

Acceptability

Universally Accepted

Official HMRC SA302 downloaded or printed from your online account

Usually Accepted

Accountant-produced tax calculations (check with specific lender)

Rarely Accepted

Copies of tax returns, management accounts alone, bank statements alone

Common Issues

"My SA302 isn't available yet"

SA302s are only available after you file your tax return. If the tax year recently ended (after 5 April), you may need to wait until your return is filed.

Solution: File your tax return as soon as possible after 5 April. Some accountants can file within days of year-end.

"My income looks lower than expected"

Your SA302 shows taxable income after expenses and deductions. This may be lower than your gross revenue.

Solution: For future years, consider the mortgage impact when claiming expenses. Some lenders add back pension contributions.

"My years show different figures"

Income variation between years is common for self-employed people. Lenders handle this differently.

Impact: Some lenders average, some use the lower figure, some use the latest year. Your broker can advise on which approach helps you.

"I can't access my HMRC account"

If you've lost access to Government Gateway, you'll need to reset or create a new account.

Solution: Reset via GOV.UK or call HMRC. Your accountant may be able to provide the documents while you sort out access.

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