Mortgage Calculators

Which calculator should you use first?

The order in which you use these tools matters. Most first-time buyers and remortgagers benefit from running them in roughly this sequence:

1. Affordability calculator — gives you a rough borrowing ceiling based on your income, outgoings, and existing commitments. This is where to start. Without an affordability figure, every other number is academic.
2. LTV calculator — converts your deposit and target property price into a loan-to-value ratio, which determines the rate band you'll be offered. Use it to model "if I save an extra £5,000, what does that do for me?"
3. Mortgage repayment calculator — once you have a rate band in mind, this tells you the monthly cost.
4. Stamp Duty calculator — adds the SDLT (or LBTT/LTT) bill on top so you can size your full cash-at-completion requirement.
5. Buy vs Rent calculator — sanity-check the headline question: is owning actually cheaper than continuing to rent in your area for your expected stay?

The other three calculators are situational:

• Remortgage calculator — when your current fix is ending or in its last 6 months.
• Overpayment calculator — when you have spare income and want to know if accelerating capital repayment is worth it.
• Early Repayment Charge calculator — when you're considering breaking a fixed-rate deal early.

What these calculators can and cannot tell you

The calculators model the maths exactly — they apply standard UK lender formulas to the figures you enter. What they cannot do:

• Tell you the rate you will actually be offered (that depends on the lender's underwriting of your specific profile).
• Account for product fees, valuation, legal, survey, and insurance costs (factor those in separately).
• Compare specific lender products against each other (that's a broker's whole-of-market search).
• Tell you whether to fix for 2, 3, 5, or 10 years (that's a regulated-advice question).

Use the calculators to scope your purchase, then get matched with an FCA-authorised broker who will give you the actual rate you qualify for and structure your application to the most suitable lender. The broker matching is free — they're paid by the lender, not by you.

UK mortgage context for 2026

These calculators assume the UK mortgage environment as of May 2026. Key context to bear in mind:

• The Mortgage Guarantee Scheme has been permanent since July 2025, supporting widespread 95% LTV availability from major banks.
• From 18 May 2026, Lloyds Banking Group offers a 98% LTV first-time buyer product with a £5,000 flat deposit.
• First-time buyer Stamp Duty thresholds reverted on 1 April 2025: relief now applies to property up to £500,000, with 0% on the first £300,000 and 5% between £300,000 and £500,000.
• The Bank of England base rate and lender SVRs change frequently — calculator results are a snapshot, not a guarantee.

For first-time buyers, our pillar guide First-Time Buyer Mortgage: The Complete UK Guide for 2026 walks through the schemes, deposit, borrowing capacity, and process in detail.