How Much Can I Borrow for a Mortgage? Understanding Affordability

One of the first questions people ask when they begin looking for a mortgage is, "How much can I borrow?" While it's a sensible place to start, the answer isn't always as straightforward as multiplying your salary by a fixed number.

Mortgage lenders look at far more than just your income. They want to be confident that you can comfortably afford your monthly mortgage payments not only today, but in the future if circumstances change.

Here's what you need to know.

It's about affordability, not just income - Many people have heard that you can borrow around four to five times your annual income. While income multiples still play a part, they are only one piece of the puzzle.

Every lender has its own affordability assessment, which considers your overall financial situation, including:

Your income
Your regular household expenditure
Existing loans and credit commitments
Credit card balances
Childcare costs
Number of dependants
Future changes to your circumstances
The size of your deposit
The mortgage term
The interest rate and how payments might change in the future

This means that two people earning the same salary could receive very different borrowing offers.

What counts as income?

Lenders are often able to consider more than just your basic salary. Depending on your circumstances, they may also consider:

Bonuses
Overtime
Commission
Self-employed income
Pension income
Rental income
Certain state benefits
Investment income

Each lender has different criteria regarding which income sources they accept and how much of that income they will use in their calculations.

If you're self-employed, most lenders will want to see at least two years' accounts or tax calculations, although some will consider applicants with only one year's trading history.

Your monthly commitments matter - Affordability isn't simply about what you earn—it's also about what you spend.

Lenders will look at regular commitments such as:

Personal loans
Car finance
Credit card repayments
Student loan deductions
Child maintenance
Nursery or childcare fees
Ground rent & service charge costs on leasehold properties
Other ongoing financial commitments

They'll also make reasonable allowances for everyday living costs such as food, utilities, transport and council tax.

Reducing existing borrowing before applying for a mortgage can sometimes improve affordability, although it's important not to make financial decisions without understanding the wider impact.

Stress testing your mortgage - Lenders don't just check whether you can afford the mortgage at today's interest rate. They also carry out what's known as a stress test. This assesses whether you could still afford your mortgage if interest rates were to increase in the future or your circumstances changed. The purpose is to help ensure you won't become financially stretched if monthly payments rise.

Your credit history still matters - A good credit history doesn't necessarily increase the amount you can borrow, but it can improve the range of lenders and products available to you.

Lenders will usually review:

Your credit score and credit report
Missed or late payments
Defaults or County Court Judgments (CCJs)
Existing levels of borrowing
How you've managed credit over time

If your credit history isn't perfect, don't assume a mortgage is out of reach. Many lenders specialise in helping borrowers with previous credit issues.

First-time buyers - For first-time buyers, affordability can often be the biggest hurdle. It's worth remembering that your monthly rent isn't always a good guide to what a lender will allow you to borrow. Mortgage affordability assessments use their own calculations, which may produce a different result than expected.

Obtaining an Agreement in Principle before viewing properties can give you a clearer idea of your budget and demonstrate to estate agents that you're a serious buyer.

Every lender is different - One of the biggest misconceptions is that every lender will lend the same amount. Borrowing limits can vary significantly between lenders. One lender may be comfortable lending considerably more than another, even when assessing the same applicant. This is where independent mortgage advice can make a real difference. Rather than relying on a single bank's affordability calculator, an independent mortgage adviser can compare a wide range of lenders to identify those whose criteria best suit your circumstances.

How we can help - Whether you're buying your first home, moving house or remortgaging, understanding what you can comfortably borrow is an important first step.

At Dentons Mortgages, we take the time to understand your financial situation and explain your options clearly. We compare mortgages from across the market to help find a lender whose affordability criteria fit your circumstances, giving you confidence before you begin your property search.

If you'd like to find out how much you could realistically borrow, we'd be delighted to help with an initial, no-obligation conversation.

Although every effort has been made to ensure that the information provided in this article is accurate and correct, the information provided does not constitute any form of financial advice. We recommend that you speak to a mortgage adviser before making any financial decisions.