Mortgage Switching Savings Calculator

Who this is for

See whether switching mortgage really saves money. Each quote is set against the payment you would make by staying, over that deal's fixed period, after fees, any exit charge and cashback, with the month the switch pays for itself.

Homeowners whose fixed or discounted rate is ending, borrowers offered a new deal by their own lender, and anyone weighing a broker's quotes against staying where they are.

What this helps you track

• The payment you would make if you stayed, as your lender states it
• Each option's monthly payment over its own fixed period
• Fees, exit charges and cashback netted off in one figure
• The month in which each switch has paid back its costs
• The steps of the switch and the date each was done

How to use it

1. Write your current lender and deal, the balance, the date the deal ends and the monthly payment your lender says you would pay if you stayed.
2. Give each quote a row: the lender and product, the fixed period in months and the monthly payment exactly as quoted.
3. Enter that option's fees, any cashback, and the exit charge your current lender would take if you left on the planned switch date.
4. Saved a month, net saving and break-even month are worked out in the browser and the workbook; on paper, multiply the monthly difference by the months and take off the costs.
5. Tick the steps as you go and write the date beside each, and read the offer documents before you commit.

Formats

• Printable PDF (A4 and US Letter)
• Fillable PDF with form fields
• Fill in online, saved in your browser
• Excel / Google Sheets workbook

The printable is laid out inside a box that fits both A4 and US Letter, so the two files are identical and neither one is scaled. The fillable PDF has real form fields. The workbook uses plain formulas only — SUM, IF, COUNTIF and the like — so it opens in Excel, LibreOffice and Google Sheets without anything breaking, and every calculated cell is grey so you can see which figures it worked out.

How to print

Download the A4 or US Letter file to match the paper in your printer, open it in a PDF reader and print at 100% — not "fit to page", which shrinks the writing space. Both files leave a 14 mm margin, which clears the unprintable edge on home printers. To print the online version with your entries in it, use the Print this sheet button, which prints only the sheet and none of the page around it. More on printing.

Questions

What is the payment if I stay?

The monthly payment your current lender says you would pay once your deal ends, or the payment on the new deal they offer you. Ask them for it; the sheet does not work it out from a rate.

How is the net saving worked out?

The monthly difference between staying and the option, times that option's fixed months, less its fees and any exit charge, plus any cashback. A minus figure means the option costs more than staying over that period.

What does the break-even month show?

The month in which the lower payments have covered the fees and exit charge, less any cashback. If an option has no monthly saving, the column stays blank, because the payments never pay its costs back.

How do I compare a short deal with a longer one?

Their net savings cover different lengths of time, so divide each by its months for a rough figure per month, and think about what happens when the shorter deal ends. The sheet does not guess at future rates.

How is this different from the mortgage offer comparison spreadsheet?

That sheet compares new offers with each other. This one measures each offer against staying with your current lender, and brings in exit charges, cashback and the break-even month.