Risk warning: Don't invest unless you're prepared to lose all the money you invest. Peer-to-peer lending is a high-risk investment and is not covered by the Financial Services Compensation Scheme (FSCS). You are unlikely to be protected if something goes wrong. Take 2 minutes to learn more.

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P2P income calculator

A target rate looks great until you account for the loans that don't pay. Enter an amount, a rate and an assumption for bad debt to see a more honest picture of the income you might keep.

Last reviewed May 2026 · by Gareth Hoyle

Illustrative income from a P2P ISA

Gross interest / yr

£700

After assumed bad debt / yr

£500

Roughly per month

£42

A simple illustration: net figures assume bad debt reduces your return by the percentage you enter. Real outcomes are lumpier than this, can be worse in a downturn, and your capital is at risk. Tax-free inside an ISA. Illustrative only, not a forecast or advice.

Why the bad-debt input matters

Headline target rates are quoted before defaults. In the real world, some borrowers don't repay, and that bad debt comes straight off your return. Putting in even a modest bad-debt assumption shows why a higher target rate is not the same as a higher guaranteed income. Actual losses are unpredictable and can be far worse in a downturn, and your capital is at risk.

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How we keep this honest

peertopeerisa.co.uk is independent. We provide general information and comparison only, not regulated financial advice. Peer-to-peer lending is a high-risk investment: your capital is at risk and your money is not FSCS protected. Some links are affiliate links, which never affect what we write.