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Fixed Cash ISA Account

Fixed Cash ISA - Your Path to Tax-Free Savings

Apply for your 2025/26 ISA before 31 March – or learn about our 2026/27 ISA, so you’re ready to fund from 6 April!

Choose ISA Tax Year
Choose Tax Year

Decide which ISA you’d like to apply for:

What is a Fixed Cash ISA?

A Fixed Cash ISA is a simple, tax-free way to grow your savings. Apply by 31 March to make the most of your 2025/26 allowance – your ISA will be ready in time for the current tax year.

Open a 2025/26 ISA Before 31 March
Rates Icon
Interest Rate

4.00% tax-free/AER

Term

2025/26 tax year 

Saving
Deposit

Between £5 and £20,000

What is a Fixed Cash ISA?

A Fixed Cash ISA is a simple, tax-free way to grow your savings. A form to pre-register will be available soon – your account will be ready to fund from 6 April at 3.85% AER for the 2026/27 tax year.

Pre-Register Now - Deposit from 6 April
Rates Icon
Interest Rate

3.85% tax-free/AER

Term

2026/27 tax year

Saving
Deposit

Between £5 and £20,000

Why Choose a Fixed Cash ISA?

Tax-Free Returns

Fixed Cash ISAs offer the benefit of tax-free interest, allowing you to make the most of your savings without worrying about deductions. This makes them an ideal choice for anyone looking to maximise their returns simply and effectively.

Fixed Rates for Certainty

With a Fixed Cash ISA, you’ll enjoy a guaranteed interest rate for the term of the account. This ensures that your savings grow reliably and eliminates any uncertainty about potential changes in rates.

Encourages Long-Term Saving

Opting for a Fixed Cash ISA often involves committing your funds for a fixed period, fostering healthier saving habits while creating an opportunity for steady financial growth.

Purpose-Driven Saving

Every pound you save supports vital roles in our community, creating a positive impact alongside your returns.

Trust and Reliability

Your savings are protected by the FSCS (Financial Services Compensation Scheme), providing you with security and peace of mind.

Woman smiling confidently, showcasing the advantages of a Fixed Cash ISA.

Summary Box for 2025/26 Fixed Cash ISA

Here’s a quick rundown of the key points about our Fixed Cash ISA, so you have everything you need to know before applying.

Account name

Fixed Cash ISA 2025/26

What is the interest rate?

4.00% tax-free/AER

Can Serve and Protect change the interest rate?

No, the interest rate is fixed for the 2025/26 tax year.

What would the estimated balance be at the end of the tax year, based on a £20,000 deposit?

If you added £20,000 to your Fixed Cash ISA on 6th April 2025 and made no withdrawals, then at 5th April 2026, your balance would be £20,800.

How do I open and manage my account?

To open an account, you must: 

  • Be aged 18 or over 
  • You must be a member of Serve and Protect
  • A UK tax resident or works as a Crown employee serving overseas and is paid out of the public revenue of the UK – typically a serving member of the armed forces or a diplomat, if they are not resident in the UK
  • Or be married to, or in a civil partnership with, an eligible person

You can open an account:

  • Online by completing an application here
  • You must deposit at least £5 to open your Fixed Cash ISA

How do I manage this account and get in contact?

  • You can manage your account through online banking, through our mobile app, and over the phone

How do I pay into this account?

If you’re using your annual ISA allowance

You can pay your initial deposit(s) into this account by transfer from another account held with another provider or us.

If you’re transferring an existing cash ISA you have (with us or elsewhere) to this account

You can do this by providing us with a completed Cash ISA Transfer Authority Form. You’ll receive the form shortly after completing our application form. Return it to us, and we’ll arrange the transfer on your behalf.

You must not withdraw the funds yourself to transfer to this account, as they will lose their tax-free status.

Can I withdraw money?

Yes – however, any withdrawals will automatically close your Fixed Cash ISA. You can take money out and close your Fixed Cash ISA whenever you wish, with no notice, although our standard 60-day interest penalty will apply for withdrawals made before the agreed subscription term.

Additional information

You might need to pay tax on the interest or dividend you receive from your savings accounts with us. This will depend on your personal financial situation. You can find more information here.

Interest will be paid into your account, and you are responsible for declaring any relevant amount of interest to the relevant authorities.

Those members residing overseas will be included in the Automatic Exchange of Information return as required by HMRC, which discloses interest payments made.

You may transfer your money to another available Serve and Protect Credit Union account or withdraw it to another account.

Are you ready to open a 2025/26 ISA? Click here to get started

Summary Box for 2026/27 Fixed Cash ISA

Here’s a quick rundown of the key points about our Fixed Cash ISA, so you have everything you need to know before applying.

Account name

Fixed Cash ISA 2026/27

What is the interest rate?

3.85% tax-free/AER

Can Serve and Protect change the interest rate?

No, the interest rate is fixed for the 2026/27 tax year.

What would the estimated balance be at the end of the fixed term, based on a £10,000 deposit?

If you added £20,000 to your Fixed Cash ISA on 6th April 2026 and made no withdrawals, then at 5th April 2027, your balance would be £20,794.

This example is for illustration purposes only.

How do I open and manage my account?

You will soon be able to pre-register online by completing an application form, so watch this space. We’ll set up your Fixed Cash ISA so it is ready to fund from 6 April 2026, when the new tax year begins.

To open an account, you must:

  • Be aged 18 or over
  • You must be a member of Serve and Protect
  • A UK tax resident or works as a Crown employee serving overseas and is paid out of the public revenue of the UK – typically a serving member of the armed forces or a diplomat, if they are not resident in the UK
  • Or be married to, or in a civil partnership with, an eligible person

How do I manage this account and get in contact?

  • You can manage your account through online banking, through our mobile app, and over the phone

How do I pay into this account?

You can fund your account from 6 April 2026, when the 2026/27 tax year begins. You can deposit money using your ISA allowance or transfer an existing Cash ISA from another provider.

If you’re using your annual ISA allowance

You can pay your initial deposit(s) into this account by transfer from another account held with another provider or us.

If you’re transferring an existing cash ISA you have (with us or elsewhere) to this account

You can do this by providing us with a completed Cash ISA Transfer Authority Form. You’ll receive the form shortly after completing our application form. Return it to us, and we’ll arrange the transfer on your behalf.

You must not withdraw the funds yourself to transfer to this account, as they will lose their tax-free status.

Can I withdraw money?

Yes – however, any withdrawals will automatically close your Fixed Cash ISA. You can take money out and close your Fixed Cash ISA whenever you wish, with no notice, although our standard 60-day interest penalty will apply for withdrawals made before the agreed subscription term.

Additional information

You might need to pay tax on the interest or dividend you receive from your savings accounts with us. This will depend on your personal financial situation. You can find more information here.

Interest will be paid into your account, and you are responsible for declaring any relevant amount of interest to the relevant authorities.

Those members residing overseas will be included in the Automatic Exchange of Information return as required by HMRC, which discloses interest payments made.

You may transfer your money to another available Serve and Protect Credit Union account or withdraw it to another account.

Are you ready to pre-register to open a 2026/27 ISA? Click here to get started.

Ready to Apply for our 2025/26 ISA?

Complete the form below to apply for your 2025/26 Fixed Cash ISA and make the most of your tax-free allowance – applications close on 31 March. 

Our 2026/27 ISA will be Ready to Apply for Soon!

Keep an eye on this page as you’ll soon be able to pre-register for our 2026/27 ISA. We’ll set up your account in advance so it’s ready to fund from 6 April 2026.

Your Savings Are Safe

Feel secure knowing your savings are protected. With Serve and Protect, your funds are covered up to £120,000 by the Financial Services Compensation Scheme (FSCS). This means you can save with us confidently, knowing your money is in safe hands.

Learn More About FSCS Protection

Helping You Understand Savings Terms

We know financial jargon can be confusing, so we’ve simplified some of the key terms you might come across:

AER (Annual Equivalent Rate)

Interest earnings if compounded annually.

Fixed Interest

Fixed interest is a rate of return on savings or investments that remains constant throughout a set period, regardless of market fluctuations. It provides stability and allows for easier financial planning.

Interest Rate

The interest rate is the percentage paid for keeping money in your savings account, helping your balance grow over time.

Maturity

Maturity marks the end of your account’s term. At this point, you can withdraw, reinvest, or explore other options.

Tax Free

Interest earned exempt from taxes, often applicable to ISAs.

Tax Year

The tax year is the 12-month period used by the government for calculating an individual’s tax liabilities. In the UK, the tax year runs from 6 April of one year to 5 April of the following year.

Confused by financial jargon? Visit our Jargon Buster for more helpful explanations.

Archived Rates

Below, you’ll find an archive of the Fixed Cash ISA rates we’ve paid, allowing you to easily track what was provided and when.

Tax yearEffective periodAER (Annual Equavalent Rate)
2025/202606.04.2025 - 05.04.20264.00%
2024/202506.04.2024 - 05.04.20254.00%

Standard ISA Rate – Our Standard ISA rate is currently 1%. This is the rate you will receive on any Cash ISAs held with us from previous tax years.

Shield
New Fixed Saver!

Secure a guaranteed 4% AER return over a 12-month term (T&Cs apply) with our latest fixed-rate savings account. Applications close Monday 30th March. Click here to learn more.