3-year fixed rate cash ISAs

Discover all you need to know about 3-year fixed-rate ISAs and compare accounts with interest rates up to 4.56% AER.

FSCS logo
Is my money safe?

The Financial Services Compensation Scheme (FSCS) guarantees that it will step in to compensate the first £85,000 (£170,000 for a joint account) you have saved with a UK-authorised bank, building society or credit union in the event that the business goes bust.

Compare 3-year fixed rate cash ISAs

Table: sorted by interest rate, promoted deals first
1 - 10 of 31
Name Product Interest rate Invest Interest paid Withdrawals Open via Deposit protection Open via Incentive Table product description Apply link
Cynergy Bank – Loyalty Fixed Rate Cash ISA
4.56% AER fixed for 3 years
From £500
Anniversary of account opening
Withdrawals not permitted
Website
FSCS logo
protected
Open via: website
Go to site
View details
United Trust Bank – Cash ISA 3 Year Bond
United Trust Bank – Cash ISA 3 Year Bond
4.55% AER fixed for 3 years
From £5,000
Anniversary of account opening
Instant access (charge applies )
Website
FSCS logo
protected
Open via: website
Go to site
View details
Cynergy Bank – Fixed Rate Cash ISA
4.55% AER fixed for 3 years
From £500
Anniversary of account opening
Withdrawals not permitted
Website
FSCS logo
protected
Open via: website
Go to site
View details
Close Brothers Savings – 3 Year Fixed Rate Cash ISA
Close Brothers Savings – 3 Year Fixed Rate Cash ISA
4.55% AER fixed for 3 years
From £10,000
Yearly
Withdrawals not permitted
Website
FSCS logo
protected
Open via: website
Go to site
View details
Shawbrook Bank – 3 Year Fixed Rate Cash ISA Bond Issue 57
4.48% AER fixed for 3 years
From £1,000
Monthly
Instant access (charge applies )
Website
FSCS logo
protected
Open via: website
Go to site
View details
Shawbrook Bank – 3 Year Fixed Rate Cash ISA Bond Issue 57
4.48% AER fixed for 3 years
From £1,000
Anniversary of account opening
Instant access (charge applies )
Website
FSCS logo
protected
Open via: website
Go to site
View details
Paragon Bank – 3 Year Fixed Rate Cash ISA
4.35% AER fixed for 3 years
From £500
Anniversary of account opening
Instant access (charge applies )
Website, post
FSCS logo
protected
Open via: website, post
Go to site
View details
Paragon Bank – 3 Year Fixed Rate Cash ISA
4.35% AER fixed for 3 years
From £500
Monthly
Instant access (charge applies )
Website, post
FSCS logo
protected
Open via: website, post
Go to site
View details
Principality BS – 3 Year Fixed Rate Cash ISA (Issue 348)
4.3% AER fixed for 3 years
From £500
Anniversary of account opening
Withdrawals not permitted
Branch, website, post
FSCS logo
protected
Open via: branch, website, post
Go to site
View details
Principality BS – 3 Year Fixed Rate Cash ISA (Issue 348)
4.3% AER fixed for 3 years
From £500
Monthly
Withdrawals not permitted
Branch, website, post
FSCS logo
protected
Open via: branch, website, post
Go to site
View details
loading

Fixed-rate cash ISAs typically have terms of between 1 and 5 years. Generally speaking, the longer the term, the higher the rate but the greater the commitment.

You’re committing to leaving your money in one place for the duration of the fixed-rate term. Technically you can withdraw your money, but will almost always incur a penalty, so it’s not something to be entered into without careful consideration.

If you opt for a 3 year fixed-rate cash ISA then you might find rates that are better than at the shorter end of the spectrum, though that’s not always the case.

What is a 3-year fixed-rate cash ISA?

Fixed-rate ISAs are a type of cash ISA. Unlike an instant access account with a variable rate, the rate is locked in for 3 years and you can’t withdraw funds without incurring a penalty. This means that you’re really committing to leaving your money alone to grow for 3 years.

You’re allowed to pay up to £20,000 into ISAs each tax year.

Bear in mind that if you put a lump sum in a 3-year account now and rates end up rising in a year, your savings could miss out on the upturn. But the reverse is also true: if interest rates end up falling over the next year, you might be happy that you locked in when you did.

Can I add more money during the 3-year term?

Generally no. You will normally be given a window of time (usually several days or weeks) to deposit funds into the account, and after that time has passed, you can’t add any more money.

From the banks’ point of view, they don’t know what rates will look like in the future. This means that fixed-rated accounts tend to offer an agreed amount based on what interest rates are today.

From the bank’s perspective, if it had promised you a fixed rate and then was happy for you to add more funds while interest rates were falling, the bank would be paying over the odds on an increasing pot of money. A smart bank will always trying to stay ahead of the game and limit the risk it’s exposing itself to.

BUT, thanks to a rule change in April 2024, you can pay into more than one cash ISA in any tax year. So if you miss the window to add more money to a fixed-rate cash ISA, you could always open another one.

Early withdrawal penalties can be harsh, so make sure you’re comfortable leaving your savings alone until your fixed-rate account matures.”

Katherine Denham, award-winning personal finance expert

Which are the best 3-year fixed-rate cash ISAs at the moment?

Our best fixed-rate cash ISAs have the highest interest rates. To get the latest rates, we use Moneyfacts data, which covers nearly the full market of savings products and is checked and updated daily. We don’t include accounts from private banks.

All the cash ISAs in our list have savings protection – for most, this is the Financial Services Compensation Scheme (FSCS). Other schemes include that of NS&I, which is 100% backed by HM Treasury, and the Gibraltar Deposit Guarantee Scheme.

  • Cynergy Bank – Loyalty Fixed Rate Cash ISA - 4.56%
  • Close Brothers Savings – 3 Year Fixed Rate Cash ISA - 4.55%
  • United Trust Bank – Cash ISA 3 Year Bond - 4.55%
  • Cynergy Bank – Fixed Rate Cash ISA - 4.55%
  • Shawbrook Bank – 3 Year Fixed Rate Cash ISA Bond Issue 57 - 4.48%

An overview of our 3-year fixed-rate cash ISA comparison

Rates up to 4.56% AER
Number of accounts 33
Minimum investment £1
Opening options Branch, website, mobile app, post, telephone

Pros and cons of 3-year fixed ISAs

Pros

  • You can usually get a better rate than on instant access or short-term accounts…
  • …and it’s tax-free!
  • The rate is fixed until your account matures, so if market rates come down, yours won’t.
  • If your circumstances change, then legally you are allowed to withdraw your funds (however you’d incur a penalty in doing so).

Cons

  • You’ll need to leave the funds to grow for the full 3-year term (or incur a penalty).
  • If interest rates rise over the 3 years, the rate on your account won’t.
  • You won’t be able to add more funds during the 3-year term.

Frequently asked questions

We show offers we can track - that's not every product on the market...yet. Unless we've said otherwise, products are in no particular order. The terms "best", "top", "cheap" (and variations of these) aren't ratings, though we always explain what's great about a product when we highlight it. This is subject to our terms of use. When you make major financial decisions, consider getting independent financial advice. Always consider your own circumstances when you compare products so you get what's right for you. Most of the data in Finder's comparison tables has the source: Moneyfacts Group PLC. In other cases, Finder has sourced data directly from providers.
Katherine Denham's headshot
To make sure you get accurate and helpful information, this guide has been reviewed by Katherine Denham, a member of Finder's Editorial Review Board.
Chris Lilly's headshot
Written by

Head of publishing

Chris Lilly is Head of publishing at finder.com. He's a specialist in personal finance, from day-to-day banking to investing to borrowing, and is passionate about helping UK consumers make informed decisions about their money. In his spare time Chris likes forcing his kids to exercise more. See full bio

Chris's expertise
Chris has written 612 Finder guides across topics including:
  • Loans & credit cards
  • Building credit
  • Financial health

More guides on Finder

Go to site