The changes come as the prizes on the firm’s flagship Premium Bonds product have reduced.
National Savings & Investments (NS&I) has ramped up the interest rates on its British Savings Bonds in response to rising rates across the market.
These bonds come in two varieties: Guaranteed Growth Bonds, which earn a fixed rate of interest over a set period of time, and Guaranteed Income Bonds, which pay out monthly income at a fixed rate of interest.
Savers can now get a 4.5% gross rate on the one-year Guaranteed Growth bond, up from 4.07% in January, while the income option has risen from 4% flat to 4.41%.
At the longer end, investors willing to put their cash away for longer will receive a lower rate (4.4% and 4.32% respectively), although both are higher than they were in January.
Savers should note that money cannot be withdrawn early from fixed-term accounts. Savers can invest anywhere from £500 to £1m in these bonds per person.
“Today’s rate increases reflect changes in the wider market and will help NS&I to meet its net financing target while continuing to balance the interests of savers, taxpayers and the broader financial services sector,” the firm said.
The changes come as the prizes on the firm’s flagship Premium Bonds product have reduced. From April 2026, the average interest rate on the bonds dropped to 3.3% from 3.6% in August 2025. A saver’s odds of winning also fell from 22,000 to one to 23,000 to one as the total number of prizes fell.
Each £1 bond purchased is entered into a monthly prize draw, where prizes range from £25 to £1m, meaning some savers may receive nothing, while others can win much more. The amount that can be saved per person is capped at £50,000, although winnings are tax-free.