Premium Bonds vs Cash ISA: Which One Actually Pays More in 2026?
The Premium Bonds prize fund rate is 3.30%. Top Cash ISAs pay 4.62%. Yet half of all bondholders win less than the headline rate suggests. The maths is brutal and almost nobody explains it honestly.
Expected annual return on £10,000
Median bondholder typically wins less than the mean. The prize fund rate is misleading at low balances.
Which product wins for you
| Your situation | Better choice |
|---|---|
| Under £20k savings, basic-rate | Cash ISA |
| Under £20k savings, higher-rate | Cash ISA |
| ISA used, £20k to £50k, higher or additional rate | Premium Bonds |
| Cash over £85k, want sovereign-backed | Premium Bonds |
| Saving for emergency fund or known goal | Cash ISA |
| Would otherwise gamble the money | Premium Bonds |
Rates as of May 2026. Top Cash ISAs around 4.6% AER, Premium Bonds prize fund 3.30% (3.80% from July 2026).
Key takeaways
Premium Bonds pay a 3.30% prize fund rate (rising to 3.80% from the July 2026 draw). Top easy-access Cash ISAs pay around 4.6% AER. Both are tax-free.
The prize fund rate is the average return across all bondholders. The median bondholder wins significantly less, because a handful of large prizes drag the mean upwards.
Premium Bonds are uniquely backed by HM Treasury through NS&I, so there is no £85,000 FSCS cap. They are useful sovereign-backed exposure above £85k.
A Cash ISA almost always beats Premium Bonds on expected return for balances under £20,000. Premium Bonds make sense for high earners who have already used their ISA allowance.