4.75% AER (variable)*. Grow your savings with confidence, with the Moneybox Cash ISA.

  • Save up to £20,000 a year with tax-free interest

  • Open with £500

  • Up to 3 withdrawals every 12 months without impacting your rate

Open or transfer an account in minutes and join over 1.5 million people saving with Moneybox.

ISA and tax rules apply. *Interest rate subject to conditions, includes 1.30% bonus rate for first 12 months. New customer rate as of 27/05/2026.

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What is a Cash ISA?

A Cash ISA is an individual savings account that you can use to earn interest on your money. You can save up to £20,000 into a Cash ISA each tax year, and the interest you earn is completely tax-free.

With the Moneybox Cash ISA, you’ll earn 4.75%* AER (variable) on balances of £500 or more, which includes a bonus rate of 1.30% for your first 12 months.

*Rate conditions apply.

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How does the Moneybox Cash ISA work?

You pay money into your Cash ISA, up to £20,000 each tax year, and earn interest tax-free. With Moneybox, you open your account from £500, add money whenever it suits you, and watch your savings grow in the app.

The tax year runs from 6th April to 5th April. Your £20,000 allowance doesn't roll over, so anything you don't use by 5th April is lost for that year. You can add money through a one-off payment, or by setting up a regular deposit. ISA and tax rules apply.

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How to open a Cash ISA

  • You can open a Cash ISA in minutes with Moneybox. Simply sign up via the website or download the app, and deposit a minimum of £500 to get started.

  • Have an ISA elsewhere? Earn 4.75% on funds transferred into a Moneybox Cash ISA. There’s no paper forms and we handle it all from start to finish, so you don’t have to.

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Build the savings you want

Grow your savings

Save in a way that works for you with weekly, monthly, and one-off deposits.

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Maximise your ISA allowance

Achieve your financial goals and make the most of your £20,000 annual ISA allowance each tax year.

Transfer an ISA in from elsewhere

Start a transfer in minutes and bring an ISA you hold elsewhere into a Moneybox Cash ISA.

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Choose a Cash ISA that suits you

Cash ISA

Our top-paying Cash ISA rate.

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Open Access Cash ISA

Unlimited withdrawals.

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Compare the Moneybox Cash ISAs

See which Cash ISA suits you.

Cash ISA

Open Access Cash ISA

Withdrawal restrictions

3 withdrawals annually

without impacting your rate

Unlimited withdrawals

no restrictions

Total interest rate

4.75% AER (variable)

includes 12 month bonus rate

4.00% AER (variable)

includes 12 month bonus rate

Bonus rate

1.30% AER (variable)

for the first 12 months

0.75% AER (variable)

for the first 12 months

Rate for transfers

4.75% AER (variable)

your underlying and bonus rate

3.25% AER (variable)

your underlying rate

Minimum balance

£500

to keep rate

£1

to keep rate

Interest payments

Yes

paid monthly

Yes

paid monthly

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Everything you need to know

What's the account name?

Moneybox Cash ISA

What's the interest rate?

Introductory rate of 4.75% AER (variable) including an additional 1.30% AER bonus interest rate for 12 months

Underlying rate of 3.45% AER (variable)

This assumes you make fewer than four withdrawals within each 12 month period from the date of opening your Cash ISA; and maintain a balance of £500 or more.

Interest is calculated daily on cleared balances and earned but unpaid interest. Your interest will be paid monthly.

You may receive an introductory bonus interest rate for a limited period from account opening. Where applicable:

  • This bonus interest rate is added to the underlying interest rate to produce a higher headline rate displayed in the app.

Bonus eligibility is determined when you open your Cash ISA account and is not applied retrospectively.

The bonus interest rate:

  • is fixed

  • may be withdrawn if conditions are not met

  • expires after 12 months from account opening

After expiry, all balances in your Cash ISA earn the underlying interest rate.

Can Moneybox change the interest rate?

  • Yes – the underlying interest rate is variable, so it can go up or down.

  • We will inform you as soon as possible of any change to the interest rate.

  • Your interest rate will also change to the lower interest rate exclusive of any bonus interest rate if:

    • Your Cash ISA balance is below £500; or

    • You make four or more withdrawals from your Cash ISA account within each 12 month period from the date of opening your Cash ISA.

  • You’ll receive the lower rate exclusive of any bonus interest rate for the rest of that period after you’ve made four or more withdrawals.

What would the estimated balance be after 12 and 24 months based on a £1,000 deposit?

Estimated balance after 12 months: £1,047.50 (for introductory rate including bonus rate)

Estimated balance after 12 months: £1,034.50 (for underlying rate)

This assumes that:

  • The account is opened with £1,000 deposit

  • No further deposits or withdrawals are made.

  • The product interest rate(s) stays the same for the full 12 months.

How do I open and manage my account?

  • The account is available to UK residents aged 18 or over.

  • You may only open and manage the account via the Moneybox app or Moneybox website.

  • At Moneybox, we define your Cash ISA account opening date as the date you open your product.

  • You can transfer in existing ISAs or make contributions up to £20,000 in total each tax year.

  • Joint accounts are not allowed.

Can I withdraw money?

You can withdraw from your Cash ISA at any time to your linked UK bank account in your name either as sole or joint account holder.

You can either withdraw the full balance held in your Cash ISA or withdraw part of the balance.

Please note that if you make four or more withdrawals within each 12 month period from the date of opening your Cash ISA, this will impact the interest applicable to your account. You’ll receive the lower rate exclusive of any bonus interest rate for the rest of that period after you’ve made four or more withdrawals. The number of withdrawals you can make without impacting your rate will reset yearly on the date you opened your account.

Additional information

The ISA is a government savings scheme and the rules, including tax benefits, could change in the future.

Interest is paid tax-free. This means that you do not pay income tax on the interest earned in the Cash ISA.

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Cash ISA FAQs

How does a Cash ISA work?

You pay money in, up to £20,000 across all your ISAs each tax year, and earn interest free from UK income tax. With the Moneybox Cash ISA, interest is calculated daily and paid monthly. You can open it from £500.

Is a Cash ISA worth it?

A Cash ISA keeps your savings interest free from UK income tax, which can matter if you've used up your Personal Savings Allowance. Whether it suits you depends on your circumstances. We don't offer financial advice, so seek independent advice if needed.

What's the difference between a Cash ISA and a savings account?

Both pay interest, but a Cash ISA's interest is free from UK income tax, while a standard savings account's interest counts towards your Personal Savings Allowance. A Cash ISA has a £20,000 annual allowance across all your ISAs. Tax treatment depends on individual circumstances and may be subject to change in the future. Read more about the differences in our guide Cash ISA vs savings accounts.

How many ISAs can I have?

You can hold as many ISAs as you like across different providers. Since 6th April 2024, you can pay into more than one ISA of the same type in the same tax year. Your total payments across all of them must stay within your £20,000 ISA allowance.

Can I have a Cash ISA and a Stocks and Shares ISA?

Yes. You can pay into a Cash ISA and a Stocks and Shares ISA in the same tax year, as long as your combined payments stay within the £20,000 allowance. You choose how to split it between them. When investing, capital at risk. ISA and tax rules apply. Read more about Cash ISAs vs Stocks & Shares ISAs in our guide.

Can I transfer an existing ISA to Moneybox?

Yes. You can transfer in existing ISAs to your Moneybox Cash ISA, alongside contributions up to £20,000 in total each tax year. Transferring rather than withdrawing and reopening keeps your money within the ISA wrapper.

It's important you know

*4.75% AER (variable) includes a bonus rate of 1.30% for the first 12 months. A lower rate of 0.75% AER (variable) applies if account conditions aren’t met.

Interest is accrued daily and paid into your account on the first day of each month. The rate is variable, and we’ll inform you if it changes.

Tax treatment depends on individual circumstances and may be subject to change in the future.