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Invest vs Pay Off Mortgage Calculator

Should you overpay your mortgage or invest the spare cash? Compare both strategies side by side over your remaining mortgage term.

Learn about this decision →

Calculator inputs

£
%
£

The extra amount you could either overpay or invest each month

%

UK equities have historically returned 7-10% nominal per year

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Overpay mortgage

£183,441

Invest instead

£243,022

Investing wins by

£59,580

Mortgage cleared

16yr 11mo

8yr 1mo early

Interest saved

£47,708

Breakeven return

4.44%

Investment return needed to beat overpaying

Important: Investment returns are not guaranteed. Overpaying your mortgage gives a risk-free return equal to your mortgage rate (4.5%). Investing offers higher expected returns but with the risk of loss, particularly over shorter periods. Consider your risk tolerance before deciding.

Net wealth comparison

£243k£132k£22k-£89k-£200k0510152025
Overpay mortgage Invest instead

Year-by-year breakdown

Year Overpay Invest Difference
1-£191,894-£191,852+£43
2-£183,416-£183,231+£185
3-£174,548-£174,109+£439
4-£165,273-£164,456+£818
5-£155,572-£154,238+£1,334
6-£145,425-£143,421+£2,004
7-£134,812-£131,969+£2,844
8-£123,712-£119,841+£3,870
9-£112,101-£106,997+£5,104
10-£99,958-£93,392+£6,566
11-£87,256-£78,977+£8,279
12-£73,971-£63,704+£10,267
13-£60,075-£47,518+£12,557
14-£45,541-£30,362+£15,179
15-£30,339-£12,175+£18,164
16-£14,439£7,108+£21,547
17£1,412£27,555+£26,143
18£19,008£49,241+£30,233
19£37,876£72,245+£34,369
20£58,108£96,649+£38,541
21£79,803£122,543+£42,740
22£103,066£150,023+£46,957
23£128,011£179,189+£51,178
24£154,759£210,150+£55,391
25£183,441£243,022+£59,580

Important: Not Financial Advice

This calculator is provided for educational and illustrative purposes only. Freedom Isn't Free is not authorised or regulated by the Financial Conduct Authority (FCA) and does not provide financial advice, investment recommendations, or tax guidance.

The projections shown are hypothetical, assume a constant rate of return, and do not account for inflation, taxes, or fees. Actual investment returns vary and you may get back less than you invest. Past performance is not a reliable indicator of future results.

Before making any financial decisions, please consult with an independent financial adviser regulated by the FCA. For help finding an adviser, visit MoneyHelper or Unbiased.

Where links to financial products appear on this page, some may be affiliate links. See our full disclaimer for details.

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