Best 5-Year Fixed Rate ISAs for 2026

Securing Your Returns: A Complete Guide to the Best 5-Year Fixed Rate ISAs

When planning for the medium-to-long term, striking a balance between growth and absolute security can be challenging. For savers looking to lock in a guaranteed return while shielding their interest from the taxman, a 5-year fixed rate Cash ISA offers an appealing sanctuary.

By committing your funds for half a decade, you can secure top-tier market rates and protect your hard-earned savings from economic shifts.

What is a 5-Year Fixed Rate Cash ISA?

A 5-year fixed rate Cash ISA is a tax-free savings account where your interest rate is locked in for a period of five years. Because you agree to leave your money untouched for the full duration, providers—typically challenger banks and building societies—are often willing to reward your loyalty with competitive rates.

Key advantages include:

• Tax-Free Growth: All interest earned is 100% free from UK income tax, regardless of whether you are a basic, higher, or additional-rate taxpayer.
• Rate Protection: Even if the broader economic climate shifts and market interest rates drop over the next five years, your agreed rate remains completely frozen.
• FSCS Protection: Eligible deposits are protected up to £120,000 per person (or £85,000 via standard UK banking protection depending on the specific institutional group framework) under the Financial Services Compensation Scheme, ensuring absolute peace of mind.

Current Market Leaders for 5-Year Fixed ISAs

The 5-year fixed rate sector regularly features competitive offerings from specialist institutions. Top-performing accounts typically cluster around the 5.00% to 5.25% AER range:

| Provider | Headline AER (Fixed) | Minimum Deposit | Key Feature |
| :— | :— | :— | :— |
| Shawbrook Bank | 5.25% | £1,000 | Established provider, robust digital platform |
| Tandem Bank | 5.13% | £1 | Flexible ISA option with a low entry barrier |
| Castle Trust Bank | 5.12% | £1,000 | Competitive e-Cash ISA structure |
| Close Brothers | 5.12% | £10,000 | Tailored for larger lump-sum deposits |
| Skipton Building Society | 5.00% | £1 | Trusted mutual society with accessible entry |