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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Cash vs investing vs P2P returns

A rough illustration of how the same money might grow tax-free under three approaches. The point isn't precision. It's the trade-off between safety and potential return.

Last reviewed May 2026 · by Gareth Hoyle

Cash ISA£12,167
+£2,167 tax-free (4.0% p.a. illustrative)FSCS-protected, rate not guaranteed
Stocks & Shares ISA£13,382
+£3,382 tax-free (6.0% p.a. illustrative)Illustrative long-run average; value can fall
Peer to peer ISA£13,701
+£3,701 tax-free (6.5% p.a. illustrative)Target net of assumed defaults; capital at risk

Strictly illustrative, not a forecast and not advice. Uses fixed assumed annual rates with no allowance for changing rates, fees, inflation or market falls. Stocks & shares values can fall as well as rise; peer-to-peer returns are not guaranteed, are usually lower after defaults, and are not FSCS-protected. Real outcomes will differ.

Read this before you trust the numbers

Higher illustrative returns come with higher risk, not certainty. A cash ISA rate is broadly known and FSCS-protected. Stocks & shares values rise and fall. You could get back less than you put in. Peer-to-peer target rates are not guaranteed, are usually lower after defaults, and are not FSCS-protected.

Keep reading

Compare providers

Independent side-by-side comparison of UK IFISA providers: target rates, minimums, security and transfers.

P2P ISA vs cash ISA

How an IFISA compares with a cash ISA on returns, risk, access and protection. Capital at risk vs FSCS-protected savings.

Cash ISA vs S&S ISA

The classic decision: guaranteed-rate savings vs investing for growth. How to choose, and why not both.

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.