Mortgage & remortgage calculators

These tools are organised by the decision in front of you, not as a pile of widgets. Fees and early repayment charges often decide a remortgage before a small rate gap does, so the first tools are about sterling cost. A payment calculator on its own will not show that. Each tool states its assumptions, checks the inputs, and marks results as illustrative only. Nothing here is a mortgage offer.

Starter figures on several tools are the site EXAMPLE: a labelled scenario, not a market quote and not your balance. Change them. If a page mentions property tax, that tool is England and Northern Ireland residential SDLT only. Scotland and Wales use different taxes and are out of scope. Rodway Labs publishes the site. Remortgage Lab is not a lender, not a broker, and not FCA-regulated advice.

How to pick a tool

Should I switch, once fees are on the page? Start with the true-cost calculator. It puts an early repayment charge, product and legal fees, any cashback and the interest difference over a period you choose next to each other. Use it when a fix is ending or when you are tempted to leave early. It does not search lenders and it does not say you will be accepted.

Stay with this lender, or remortgage? The remortgage versus product transfer calculator is the interactive numbers only. It runs two paths on the same balance and term. For what a product transfer is, read the explained guide. For which factors to weigh before you type, read the comparison. Do not expect this hub, or that calculator, to repeat those essays.

Leaving during a deal. The ERC estimator turns the method in your offer — a percentage, or months of interest — into a figure you can drop into the true-cost tool. The offer wording still beats the estimate. The formulae are explained on how ERCs are calculated. When the charge bites, and what else to set beside it, is on early repayment charges.

Spare cash. The overpayment calculator shows interest and term if you pay extra on the rate you enter, with a warning if you might cross an allowance. The overpay-versus-remortgage calculator asks a different question: the same lump sum kept against the current loan, versus remortgaging that balance and paying fees and any ERC. One is “what does overpaying do?”. The other is “does overpaying beat leaving?”. Use the one that matches the question.

The payment itself. The repayment calculator is capital and interest on a rate and term you type. It does not include an ERC or a remortgage fee stack. Use it to check a monthly figure, then move to true cost if you are actually switching. Affordability is only an income-multiple sketch plus a note that lenders stress the payment. It is not an agreement in principle and not a borrowing offer.

Band and buying tax. LTV and equity turns a balance and a value into a percentage and the gap to a band you choose. Crossing a band does not guarantee a cheaper product. The lender’s valuation is the one that counts. Stamp duty is a purchase-tax sketch for England and Northern Ireland. A straight remortgage of your own home usually does not trigger it. Do not type the EXAMPLE mortgage balance in as a purchase price.

What every tool refuses to do

None of them pulls a live rate feed, scores your credit, or knows whether a valuation will come in low. Rates you leave as EXAMPLE starters are not today’s price. Adding a fee to the loan, where a tool offers that toggle, is a cash-versus-interest trade-off, not a recommendation to add it. Porting, further advances and offset mortgages are outside the models. The glossary defines those words. The calculators do not price them.

Read the short method note under each result before you screenshot it. If the note and your illustration use different day-count or a different balance date, expect pennies or pounds of difference. For an early repayment charge, expect the lender’s redemption statement to be the figure that gets paid. Our tools exist so you can see the shape of the arithmetic first.

Guides sit beside the tools on purpose. A long explanation of fee types is on mortgage fees explained. The remortgage-only stack is on remortgage fees. Whether to start the process, and how many months out, is on when to remortgage. The last weeks of a fix are a separate checklist. You do not need to read all of that before you change a number. You do need your own offer if you want the number to mean something.

A sensible order

If a deal is ending, note the end date and whether an early repayment charge is still live, then estimate that charge, then run true cost or the product-transfer comparison with the fees from the illustrations you actually hold. Check LTV if a valuation could move you across a band. Use the repayment tool only as a payment check. Use stamp duty only if you are buying, and only in England or Northern Ireland.

Results update as you edit. They are not stored as an application and they are not sent to a lender. For how advertising is separated from those results, see the advertising disclosure. For what this site will not do in an email, see contact.