Best 18 Month Fixed Rate Bonds in October 2026

Union Bank of India (UK) Ltd's 18 Month Union Premier Bond pays 5.12%, which sits above the market average for fixed-rate accounts, though it is 0.25% behind the current market leader at 5.37%. The rate also beats August 2026 CPI of 3.1% by 2.02%, so your money grows in real terms.

The main catch is the usual one for fixed bonds: no access until maturity, with interest paid only then. You need at least £1,000 to open and can deposit up to £480,000.

Thisbank's 15-Month Fixed Term Deposit at 5.10% sits above the market average for fixed-rate accounts, though it trails the category leader by 0.27%, who currently offers 5.37%. The rate does beat August 2026 CPI of 3.1% by 2.00%, so your money grows in real terms, which matters over a 15-month commitment.

The main catch is that you cannot touch your money until maturity, and interest is only accessible then too, so this suits savers who are confident they will not need funds between £100 and £500,000 locked away for the full term.

Aldermore's 18 Month Fixed Rate Savings Account pays 4.93%, which sits near the market average for fixed-rate accounts and is 0.44% behind the current market leader at 5.37% across all terms.

That said, 4.93% does beat August 2026 CPI of 3.1% by 1.83%, so your money is at least growing in real terms. The account needs a minimum of £1,000 and you get no access until maturity, which is the main thing to weigh up before committing.

It suits savers who want a straightforward fixed return and can leave their money untouched for eighteen months.