How Do Mortgage Lenders Calculate Your Income? What’s the Maximum They’ll Lend?

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When it comes to getting a mortgage, most people just want to know one thing: “How much can I borrow?” The answer isn’t one-size-fits-all, because lenders assess your income, outgoings, and overall financial health before deciding how much they’re willing to lend.

Let’s break it down.

 

How Do Lenders Calculate Income?

Lenders typically assess income in two main categories:

  1. Employed Applicants

If you’re employed, lenders will usually look at:

  • Your basic annual salary
  • Any guaranteed bonuses or overtime
  • Some may consider regular commission or variable income (usually averaged over 6–12 months)

 

Tip: Lenders often request 3 months’ worth of payslips and bank statements, but some may ask for more if your income varies.

 

Self-Employed or Company Directors

For self-employed applicants, lenders usually look at:

  • 1–3 years’ worth of accounts or SA302s
  • Your salary plus dividends (for company directors)
  • Some lenders may consider retained profits — but not all!

 

Tip: Having a good accountant who prepares clear, consistent accounts can make a big difference.

 

How Much Will They Lend?

Most lenders use an income multiple — typically 4 to 4.5 times your annual income, though some go up to 5 or even 6 times, depending on:

  • Your job and profession (some lenders have enhanced affordability for certain occupations)
  • Loan-to-value (LTV) — e.g., borrowing 85% vs 60%
  • Your credit score
  • Your monthly outgoings and existing debts
  • Number of dependents
  • The term of the mortgage

 

Example: If you earn £40,000 a year:

  • At 4x, you could borrow £160,000
  • At 5x, that rises to £200,000
  • At 6x, potentially £240,000 — but that’s usually reserved for low-risk, high net worth borrowers

 

What Can Affect Affordability?

Lenders don’t just look at income — they run a full affordability assessment, which factors in:

  • Credit commitments (loans, credit cards, car finance)
  • Childcare costs or school fees
  • Household bills and lifestyle expenses
  • Future interest rate increases (they “stress test” your mortgage)

This is why two people earning the same salary might be offered very different borrowing amounts.

 

 How Can You Maximise What You Can Borrow?

✅ Keep your credit score healthy
✅ Pay down existing debts
✅ Use a mortgage broker (like us!) who understands different lenders’ criteria
✅ Don’t overstate variable income — be honest and consistent

 

We’re Here to Help

Understanding how lenders assess income and affordability can be confusing, but that’s where we come in. At Oak Mortgages, we work with a wide range of lenders — including those who specialise in complex income or offer enhanced borrowing.

Get in touch today and we’ll help you understand exactly how much you can borrow — and with which lender.

 

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