Premium Bonds vs Fixed-Rate Bonds: Which Is More Tax-Efficient in 2026?

Two very different products

Premium Bonds and fixed-rate savings bonds are often mentioned in the same breath because both are seen as "safe" places to park a lump sum. In reality, they work in fundamentally different ways, and which one suits you depends heavily on your tax position.

Premium Bonds: no interest, tax-free prizes

Premium Bonds, issued by NS&I (National Savings & Investments), pay no interest whatsoever. Instead, NS&I pools the equivalent return across all bondholders into a prize fund, and every month a set number of prizes — from £25 up to two jackpots of £1 million — are drawn using a random number generator (ERNIE).

The rate NS&I uses to size that prize fund is the prize fund rate, which is variable and reviewed periodically by NS&I. Because it changes over time, always check NS&I's current published prize fund rate rather than relying on a fixed figure — what matters for planning purposes is that it represents an average return across all bondholders, not a guaranteed return for any individual saver.

Fixed-rate bonds: guaranteed interest, but taxable

A fixed-rate bond, by contrast, pays a known, guaranteed interest rate for a fixed term — commonly one, two, three or five years — in exchange for locking your money away (early access is usually restricted or penalised). The interest you earn is savings income for tax purposes, and is taxed at your marginal rate once it exceeds your Personal Savings Allowance (PSA).

The Personal Savings Allowance is the crux

This table is why the "which is better" question doesn't have one answer. A basic-rate taxpayer with modest savings may never breach their £1,000 PSA and effectively gets fixed-rate bond interest tax-free anyway — in which case the guaranteed, known return of a fixed-rate bond is usually the stronger choice, since Premium Bonds' prize-based return is inherently uncertain for any single holder, especially with smaller balances.

An additional-rate taxpayer, however, gets no PSA at all. Every pound of fixed-rate bond interest they earn is taxed at 45%. For this group, Premium Bonds' tax-free prizes become comparatively more attractive on an after-tax basis, even though the underlying return is variable and not guaranteed for any individual.

Worked example: £20,000 saved for one year

The pattern is consistent: the higher your tax band, the more of a fixed-rate bond's guaranteed return is eroded by tax, while Premium Bonds prizes are untouched regardless of band — the trade-off being that Premium Bonds returns are inherently variable and can be zero in any given month for an individual holder.

Practical guidance

• Basic-rate taxpayers with modest savings: a fixed-rate bond (or easy-access savings) often makes more sense, since the guaranteed return usually sits within your £1,000 PSA anyway.
• Higher-rate taxpayers with larger balances across several accounts: check whether other savings interest already fills your £500 PSA — if so, additional fixed-rate bond interest is taxed at 40%, making Premium Bonds worth comparing.
• Additional-rate taxpayers: with a £0 PSA, all fixed-rate bond interest is taxed at 45%. Premium Bonds' tax-free prizes (up to the £50,000 holding limit) are worth serious consideration as part of a balanced savings strategy, alongside guaranteed-return products for the portion of savings you rely on for certainty.
• Everyone: consider using your £20,000 annual ISA allowance first — a cash ISA shelters interest entirely from tax, independent of your PSA, and doesn't involve the uncertainty of a prize draw.

The bottom line

Fixed-rate bonds give you certainty; Premium Bonds give you tax-free upside with no guaranteed floor. For lower and middle earners with modest balances, the PSA often neutralises the tax question entirely, so the guarantee of a fixed-rate bond tends to win. For additional-rate taxpayers with no PSA, or anyone who has maxed out tax-efficient wrappers like ISAs, Premium Bonds' unlimited tax-free prizes become a genuinely competitive option — provided you're comfortable that your actual return could be higher or lower than the published prize fund rate in any given period.