UK Mortgage Calculator

What each input means (UK mortgage calculator)

• Property Price — the asking price of the home (e.g. £250,000).
• Deposit — what you pay upfront. You can enter it as a £ amount or as a % of the property price.
• Single rate / Two rate periods / Three rate periods — how you want to model interest: one interest rate for the whole term, or different rates for different time ranges.
• Interest rate (period 1) — the annual interest rate for the first time range.
• From / To months (period 1) — where interest period 1 starts and ends (in months). Period 1 is usually fixed from month 1.
• Interest rate (period 2) — the annual interest rate for the second time range (shown only if you selected “Two rate periods”).
• From / To months (period 2) — the month range where period 2 applies (months are set so the periods join up).
• Interest rate (period 3) — the annual interest rate for the third time range (shown only if you selected “Three rate periods”).
• From / To months (period 3) — the month range where period 3 applies.
• Repayment Type — how you repay the mortgage: “Fixed monthly payments” (same monthly payment), “Fixed capital repayments” (capital part stays the same, payment falls), or “Lump-sum repayment at the end” (interest-only until the final payment).
• Buildings Insurance (monthly) — an estimate of your buildings insurance cost (entered as £ per month, or via % mode if you use it).
• Mortgage Protection Insurance (monthly) — an estimate of your protection insurance cost (life/policy type coverage), per month.
• Service Charge (monthly) — an estimate of service/maintenance charges you’ll pay each month (e.g. for flats/estates).
• Payment Holiday Period (years/months) — how long you want to model a payment holiday.
• Add interest to the mortgage balance during the payment holiday — if ticked, unpaid interest is added to your balance during the holiday (so you end up borrowing more); if not ticked, you effectively pay the interest during the holiday.
• Deposit available (Affordability tab) — the deposit you have for affordability calculations.
• Monthly rent you will no longer pay — rent you currently pay that would stop if you buy a home (used to raise your monthly budget).
• Additional monthly disposable income — extra money you can put towards a mortgage each month.
• Estimated monthly property costs — estimated ongoing costs (so they reduce what’s available for the mortgage payment).
• Mortgage interest rate (for affordability) — annual interest rate used only for the affordability calculation.
• Mortgage Term (for affordability, years/months) — the term you assume for the mortgage in the affordability “how much can I borrow?” view.
• Stamp Duty Land Tax — SDLT estimate. Enter as £ or % using the paired inputs.
• Solicitor / Conveyancing Fees — legal/conveyancing costs estimate (pair of £ / % inputs).
• Property Survey Costs — survey/valuation costs estimate (pair of £ / % inputs).
• Mortgage Broker Fee — broker fee estimate (pair of £ / % inputs).
• Mortgage Valuation Fee — valuation/extra lender-related fees (pair of £ / % inputs).
• Other Costs — any extra one-off costs you want to include (pair of £ / % inputs).
• Other Costs (bank processing fee) — bank/admin fee estimate (pair of £ / % inputs).
• First Repayment Date — when your first mortgage repayment starts (used to label the schedule dates).
• Net Monthly Income — your take-home income used to display affordability signals (income commitment / effort rate).
• Monthly mortgage overpayment — extra amount you pay each month (used when you choose “Mortgage overpayments”).
• From (month/year) — Monthly overpayment — when those monthly overpayments start.
• Annual mortgage overpayment — extra amount you pay once per year (used when you choose “Mortgage overpayments”).
• From (month/year) — Annual overpayment — when the yearly overpayment starts.
• One-off mortgage overpayment — a single lump extra payment at the chosen date.
• In (month/year) — One-off overpayment — when that one-off payment is made.
• Add — shows additional one-off overpayment rows (so you can add multiple one-off payments).
• Overpayments list (additional £ / Month / Year rows) — extra one-off payments you’ve added, each with its own date.
• Include purchase costs to the mortgage — tick this if you want to add the selected purchase costs (fees/SDLT etc.) to the loan amount.
• With a payment holiday → Payment Holiday Period + checkbox — this whole section is only used when the “With a payment holiday” tab is selected.
• Mortgage overpayments tab → extra payments section — this whole section is only used when “Mortgage overpayments” is selected.
• How much can I borrow? → affordability result inputs — used only to estimate the maximum property price and the mortgage that fits your income/budget.