How much can I borrow for a mortgage in the UK?

Most UK lenders offer 4 to 4.5 times your annual income. On a £45,000 salary, you could borrow around £202,500. With a 10% deposit, that means a property up to roughly £225,000. Some lenders may stretch to 5× or more for high earners or specific professions.

What happens when my fixed-rate mortgage ends?

When your fixed rate ends, you'll move onto your lender's Standard Variable Rate (SVR), which is usually much higher — often 7–8%. Most people remortgage to a new fixed deal before their current one expires. Start looking 3–6 months before your fix ends to lock in a better rate.

How much can I overpay on my mortgage?

Most UK mortgage deals allow you to overpay up to 10% of your outstanding balance per year without an early repayment charge. Overpaying £200/month on a £250,000 mortgage at 4.5% over 25 years could save you over £30,000 in interest and take years off your term.

What deposit do I need for a UK mortgage?

The minimum is typically 5% of the property price, but 10%+ gets you access to better interest rates. A 15–20% deposit gives the most competitive rates. On a £300,000 property, that's £15,000 at 5%, £30,000 at 10%, or £60,000 at 20%.

UK Mortgage Calculator

How much can you borrow? What will your remortgage save? How much do overpayments help?

Your finances

Annual income

Monthly debts

Credit cards, car finance, student loan, etc.

Interest rate

Mortgage term

years

Deposit

Typical: 5–20%. 10%+ gets better rates.

—

Based on a 4.5× income multiplier. Actual lending criteria vary by lender.

How to Use This Calculator

First-Time Buyer tab

Enter your annual income (gross salary before tax), deposit amount, interest rate, and mortgage term. The calculator instantly shows your maximum borrowing, monthly repayment, and total cost over the full term. Expand "More options" to adjust the income multiplier, add a second applicant's salary, or include fees.

Remortgage tab

Enter your current outstanding balance, property value, new interest rate, and remaining term. The calculator compares your existing deal with the new one — showing how much you could save each month and over the life of the mortgage. Use "More options" to include early repayment charges and arrangement fees.

Overpayment tab

Enter your current mortgage balance, interest rate, remaining term, and monthly overpayment amount. The calculator shows how much interest you'll save and how many years you'll shave off your mortgage. Most lenders allow overpayments of up to 10% of the outstanding balance per year without penalty.

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The Formula

UK mortgage repayments are calculated using the annuity formula, which gives you a fixed monthly payment covering both interest and capital repayment over the term.

M = P [ r(1 + r)ⁿ ] / [ (1 + r)ⁿ − 1 ]

Where:
M = monthly repayment
P = principal (loan amount)
r = monthly interest rate (annual rate ÷ 12)
n = total number of monthly payments (term in years × 12)

Income multiplier

Most UK lenders use an income multiplier to determine how much you can borrow. The standard multiplier is 4.5 times your gross annual income, though some lenders offer up to 5.5× for higher earners.

Maximum Borrowing = Gross Annual Income × 4.5

Example

James — first-time buyer earning £50,000

James earns £50,000 per year and has saved a 10% deposit. He's looking at a 25-year repayment mortgage at 4.5% interest.

First-Time Buyer tab

Annual income£50,000

Income multiplier4.5×

Maximum property price£250,000

With a 10% deposit on a £250,000 property:

Deposit (10%)£25,000

Mortgage amount£225,000

Interest rate4.5%

Term25 years

Monthly repayment~£1,251

Total repaid over term~£375,300

Total interest paid~£150,300

Loan-to-value (LTV)90%

James's monthly repayment of £1,251 represents roughly 30% of his gross monthly income. Lenders typically prefer this ratio to stay below 35–40%, so he's comfortably within range.

Frequently Asked Questions

How much can I borrow? ▼

Most UK lenders will offer between 4 and 4.5 times your gross annual income. For joint applications, both salaries are combined before applying the multiplier. So if you earn £50,000, you can typically borrow up to £225,000. Some specialist lenders may stretch to 5 or even 5.5 times income for certain professions (doctors, solicitors, accountants), but you'll need a strong credit history and a larger deposit. The lender will also run an affordability assessment, factoring in your outgoings, debts, and whether you could still afford repayments if interest rates rose.

Fixed vs variable rates — which should I choose? ▼

A fixed rate locks your monthly repayment for a set period — typically 2 or 5 years. This gives you certainty: your payments won't change regardless of what happens to the Bank of England base rate. A variable rate (tracker or discounted) can go up or down with market conditions, which means lower payments when rates fall but higher payments when they rise. When your fixed deal ends, you'll usually move onto your lender's standard variable rate (SVR), which is almost always more expensive. It's worth remortgaging to a new deal before your fixed period expires.

How much should I overpay? ▼

Most lenders allow you to overpay up to 10% of your outstanding balance per year without incurring an early repayment charge. Even modest overpayments can make a significant difference thanks to compound savings — overpaying by just £100 per month on a £200,000 mortgage at 4.5% could save you over £20,000 in interest and cut roughly 4 years off your term. Check your mortgage terms before overpaying, as exceeding the limit may trigger penalty charges. If you're on your lender's SVR or a tracker with no ERCs, you can usually overpay without restriction.

What's LTV and why does it matter? ▼

LTV (loan-to-value) is your mortgage amount expressed as a percentage of the property's value. If you buy a £250,000 home with a £25,000 deposit, your mortgage is £225,000 and your LTV is 90%. LTV matters because it directly affects the interest rates available to you — the lower your LTV, the better the rates. Lenders see lower LTV as less risky. The biggest rate improvements tend to come at the 90%, 80%, 75%, and 60% thresholds. Saving a larger deposit or building equity through repayments brings you into better LTV bands over time.

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