The September rate replaced July’s 3.80%
If you still see “current Premium Bonds prize rate: 3.80%,” you are reading the July 2026 figure. NS&I raised the fund-wide rate to 4.35% from the September 2026 draw, and improved the monthly odds for each eligible £1 bond to 21,000 to 1 from July’s 22,000 to 1. Its 18 August announcement states both changes. A 4.35% prize fund rate describes the average amount allocated across all bonds over a year; it does not credit 4.35% interest to your holding.
That distinction matters if a bill is due next year. A savings account states the interest rate and terms; Premium Bonds give each eligible bond repeated chances of winning a tax-free prize. You may receive nothing in a particular month, even with a sizeable balance. There is no honest fixed “median return” for your holding in this article without a specified simulation and a checked, current distribution.
Two changes, and what the odds mean
| Draw | Prize fund rate | Monthly chance per eligible £1 bond |
|---|---|---|
| July 2026 | 3.80% | 1 in 22,000 |
| September 2026 | 4.35% | 1 in 21,000 |
Premium Bonds rate increased again in September 2026
NS&I’s September prize-allocation table records 6,529,868 prizes worth £497,086,175 in that draw, including two £1 million prizes. These are draw-wide totals, not payouts promised to any one saver. The fund allocates prize money across large, medium and small prizes; the two jackpots make individual results especially uneven. Prize rates, odds and the distribution can change again, so check NS&I before a purchase rather than carrying September’s number into a later year.
Each £1 bond in the draw has a 1-in-21,000 monthly chance of winning a prize. A £10,000 holding represents 10,000 eligible bond numbers. It has an expected number of about 10,000 ÷ 21,000 = 0.476 prizes in one draw, or 5.71 prizes across 12 eligible draws at unchanged odds. Expected number is not a probability: it can exceed one for a large holding while the probability of at least one win can never exceed 100%. The previous version of this page incorrectly labelled “227%” as a monthly win chance for £50,000. That number was a rough expected count, not a chance.
How likely is a year with no prize?
For a rough planning calculation, treat each eligible £1 bond in each draw as having a 1-in-21,000 chance and approximate the draws as independent. Under that approximation, the chance of no prize over 12 draws is (1 − 1/21,000) raised to 12 times the number of bonds. For £1,000 held throughout, the result is about 56.5%. For £5,000, it is about 5.74%; for £10,000, about 0.33%. This is a model, not an NS&I guarantee of outcomes or a replacement for the actual draw rules.
Approximate chance of no prize in 12 eligible draws
The calculation assumes the same holding is eligible in all 12 draws and the odds stay at September’s level. New bonds do not go straight into the next draw: NS&I says they must be held for a full calendar month first. If you buy partway through the year, the number of eligible draws is smaller. Holding £50,000 gives more chances than £1,000, but it never removes randomness or guarantees a particular return.
Mean prize rate versus the money you receive
Suppose Nisha holds £10,000 for a full year and uses the September rate only as a rough fund-wide expectation. Multiplying 4.35% by £10,000 gives £435. She will not receive a scheduled £36.25 every month. She might win a few £25 prizes, receive a larger prize, or receive no prizes at all. The 4.35% is not a rate that can be compared with a bank’s guaranteed annual interest without acknowledging that variation.
NS&I allows £25 minimum purchases and £50,000 maximum holdings per person. It says the original capital is backed 100% by HM Treasury and prizes are free of UK Income Tax and Capital Gains Tax. The tax-free status means a prize does not use your Personal Savings Allowance; the old image on this page incorrectly claimed that it did. A bond’s purchasing power can still fall with inflation, and a safe principal does not guarantee any real return.
A better cash-account comparison
Write down a real Cash ISA or savings-account quote you can actually open, including whether the rate is fixed or variable and when you can withdraw. A Cash ISA pays interest tax free within the relevant annual ISA rules. Ordinary savings interest may be covered by the Personal Savings Allowance or taxed, depending on total income; the government explains those thresholds. Premium Bonds prizes are tax free regardless of that allowance, but they are not monthly interest. There is no defensible “Cash ISA currently pays 4.5%” claim without a live named account and date.
The protections are different. NS&I’s Premium Bonds principal is backed by HM Treasury. Eligible deposits at a UK-authorised bank, building society or credit union are covered by the Financial Services Compensation Scheme up to £120,000 per person per authorised firm from 1 December 2025, as the FSCS states. That figure replaced the old £85,000 limit. If two bank brands share one banking licence, the limit generally applies across them together.
For money you must have on a set date, compare the bank account’s actual interest and withdrawal terms with the possibility of a zero-prize stretch. For surplus cash where you value the draw and the tax-free treatment, decide how much variability you can accept. No blanket “ISA first” or “hold the £50,000 maximum” rule fits every saver. Recheck NS&I’s prize-rate page before acting because the next draw could have different odds.
