Overpay, save or invest?
The same amount each month, five ways, side by side. Free, and nothing you type is saved.
£
To Nov 2031
£12,000 in by Nov 2031. You pay 20% tax. The ISA rows assume this year's £20,000 ISA allowance is unused.
- Certain, but tied up in your homeOverpay your mortgageAt 3.89%. You owe £13,220 less.£13,220£1,220 better off
- Certain while the rate holdsCash ISAAt 5% on £200, the highest we've compared. No tax.£13,620£1,620 in interest
- Certain while the rate holdsSavings accountAt 5% on £200, taxed above your £1,000 allowance.£13,620£1,620 after tax
- Could be more, or less than you put inStocks and shares ISAIf investments grow 5% a year. No tax.£13,620£1,620 if they do
- Could fall too. Taxed above the allowancesInvesting outside an ISAIf investments grow 5% a year.£13,620£1,620 if they do
Assumptions you can change
Investments growA year, after fees. Not a forecast.
Cash rates are the highest we compared on 17 Oct 2026, on £200, and can change. Many people keep some in easy access for emergencies. Blooom gives information, never advice.
See your own figures
Put in one account and Blooom shows what it earns, what it could earn, and every date that matters.