How Much Can I Borrow for a Mortgage? A Realistic Guide

"How much can I borrow?" is the question every buyer wants answered before they start looking at properties. The honest answer is: it depends on more than just your income. Here's the full picture.

How do lenders decide how much to lend?

Lenders combine two separate calculations:

1. Income multiples — how many times your annual income they're willing to lend
2. Affordability — whether the resulting monthly payment fits comfortably in your budget

Whichever produces the smaller number wins. So if income multiples say you can borrow £250,000 but the affordability check says you can only afford £210,000, the offer is £210,000. Most borrowers hit the affordability cap before the income multiple cap.

That's why this guide covers both. Knowing how each works lets you spot the lever you've got the most control over.

Income multiples explained

Most UK lenders offer between 4 and 4.5 times your annual income. So if you earn £40,000, the typical maximum is £160,000 to £180,000.

Some lenders go higher:

• 4.0x to 4.5x: Standard range across most mainstream lenders
• 4.5x to 5.0x: Available to borrowers with strong income, low debts and good credit
• 5.0x to 5.5x: Specialist products, often requiring a higher income (typically £60,000+) and a 10%+ deposit
• 5.5x+: Specific professional mortgages (doctors, lawyers, accountants) where the lender expects future income growth

For joint applicants, lenders usually combine both salaries. So a couple each earning £40,000 (combined £80,000) might be offered around £320,000-£360,000. Lower-earning partner's income still counts, just at the joint level.

The affordability assessment

This is where income multiples meet reality. The affordability check looks at your actual budget and stress-tests whether you can really afford the proposed repayment.

The lender looks at:

• Net income (your take-home pay — see our take-home pay calculator)
• Existing debts (loans, credit cards, finance agreements)
• Regular outgoings (utilities, council tax, insurance, transport)
• Childcare and dependants
• Any other committed spending

From that they calculate your disposable income — what's left after essentials. Then they stress-test: would you still afford the mortgage if rates rose by 2-3%? If not, they reduce the maximum loan.

This is why an affordability calculator is essential before you start looking. Our mortgage affordability calculator gives you a realistic estimate before any lender check.

What counts as income for a mortgage?

Different lenders count different things, but the typical hierarchy is:

• Basic salary: always counts in full
• Guaranteed overtime: usually counts in full
• Regular bonuses: often counted at 50-100%, depending on consistency
• Commission: averaged over the last 2-3 years, sometimes counted at less than full value
• Self-employed profit: typically averaged across 2-3 years
• Rental income: often counted at 75-100% of the gross amount
• Pensions, child benefit, tax credits: some lenders count these, others don't
• Investment income: rarely counted unless very large and stable

If a significant part of your income falls outside basic salary, it's worth using a broker — they know which lenders are most generous about counting your specific income type.

How your debts affect borrowing

Existing debts come straight off your borrowing potential. The lender's affordability calculation treats every monthly debt payment as money that can't go toward the mortgage.

For every £100 of monthly debt payments, your maximum mortgage drops by roughly £15,000-£20,000 (the exact amount depends on the term and rate they're stress-testing).

So a £200 monthly credit card payment can shave £30,000-£40,000 off your maximum loan. A £300 car finance payment can knock off £45,000-£60,000.

If you're planning to apply within the next year, paying off (or down) the smaller debts can have a big impact on the maximum mortgage. Use our loan repayment calculator to plan the timeline.

Deposit size and LTV

Loan-to-value (LTV) is the size of the mortgage divided by the property price. It doesn't directly affect how much you can borrow, but it affects what rate you'll be offered — which in turn affects affordability.

• 95% LTV: Highest rates, smallest pool of lenders
• 90% LTV: Better rates, more choice
• 85% LTV: Comfortable mainstream rates
• 75% LTV: Better still — most competitive rates
• 60% LTV or lower: Lowest rates on the market

A bigger deposit reduces the rate, which reduces the monthly payment, which increases what you can afford. So saving an extra few percent of the property price often lets you borrow a bit more and pay less per month.

Can a second applicant help?

Yes, in most cases. Adding a second applicant — partner, spouse, family member — usually combines both incomes for the affordability assessment. That can significantly raise the maximum borrowing.

The catch: both applicants' credit files are checked, and both sets of debts and outgoings are included. If your potential co-applicant has weaker credit or significant debts, the joint application can end up offered less than your solo application would have been.

Some lenders also offer "joint borrower sole proprietor" mortgages, where two people are responsible for the repayments but only one is named on the property deeds. This is most often used to help first-time buyers borrow with a parent's income supporting the application.

Self-employed mortgages and borrowing

Self-employed borrowing is harder but absolutely doable. The main hurdle is documentation: most lenders want two to three years of accounts or self-assessment tax returns (SA302s).

Some key points:

• Lenders use your net profit (after expenses), not your turnover
• If profit is declining year-on-year, lenders usually use the lower most recent figure
• Limited company directors are sometimes assessed on salary + dividends, sometimes on net profit retained in the business
• Under two years of accounts? A small handful of specialist lenders will consider you, but expect higher rates

If you're self-employed and planning to apply, talking to a broker months in advance is well worth it. Some lenders are far friendlier to self-employed borrowers than others, and a broker knows which.

How to increase your maximum borrowing

Without raising your income, the levers that increase your maximum mortgage are:

• Pay down existing debts. Especially credit cards and short-term loans.
• Reduce regular outgoings. Cancel unused subscriptions, switch to cheaper bills.
• Add a second applicant. If you have a partner with good credit, joint applications usually mean bigger mortgages.
• Save a larger deposit. Smaller LTV means better rates, which improves affordability.
• Improve your credit score. Better scores unlock more flexible lenders. Our credit improvement guide walks through how.
• Choose a longer term. A 30 or 35-year mortgage has lower monthly payments and so passes affordability tests for higher amounts (though you pay more total interest).
• Use a broker. Brokers know which lenders are most generous for your specific profile.

Most buyers can lift their maximum borrowing by 10-20% with a few months of preparation — usually enough to bridge the gap between "almost the right house" and "the right house".

Using a mortgage broker

A mortgage broker has access to deals that aren't available direct to consumers. They also know the quirks of different lenders' affordability calculations — which can mean the difference between an offer and a rejection.

Reasons to consider a broker:

• You're self-employed or have non-standard income
• Your credit history has any blips
• You want to compare a wide range of lenders without running multiple hard searches
• You don't have time to research the market yourself
• You're a first-time buyer feeling overwhelmed

Most brokers charge either a flat fee (typically £300-£700), a percentage commission (around 0.3-1% of the loan), or are paid by the lender on completion. Always ask upfront. Some "fee-free" brokers receive commission only — they're still independent if they're whole-of-market, but worth checking they're not steering you toward the lender that pays them most.

Frequently asked questions