The Flagstone Cash ISA is provided in partnership with WealthKernel, an FCA-authorised firm which manages the ISA.

Our best Instant Access Cash ISAs

One Flagstone account, multiple Instant Access options. All in one tax-free Cash ISA.

We update this table daily, so rates and banks may change. We’ve already deducted our share of the interest from these rates. 

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Results (11):

Showing 1-9

Bank name Teachers Building Society
AER | Gross 3.81% | 3.75%
Term Instant Access
Min. Deposit £1,000
Max. Deposit £120,000
Bank name Aldermore
AER | Gross 3.77% | 3.71%
Term Instant Access
Min. Deposit £5,000
Max. Deposit £10,000,000
Bank name Paragon Bank PLC
AER | Gross 3.76% | 3.70%
Term Instant Access
Min. Deposit £1,000
Max. Deposit £120,000
Bank name LHV Bank
AER | Gross 3.72% | 3.66%
Term Instant Access
Min. Deposit £10,000
Max. Deposit £120,000
Bank name OakNorth
AER | Gross 3.53% | 3.47%
Term Instant Access
Min. Deposit £1,000
Max. Deposit £1,000,000
Bank name Birmingham Bank
AER | Gross 3.45% | 3.40%
Term Instant Access
Min. Deposit £5,000
Max. Deposit £120,000
Bank name Griffin Bank
AER | Gross 3.40% | 3.35%
Term Instant Access
Min. Deposit £1,000
Max. Deposit £120,000
Bank name Arbuthnot Direct - Part of Arbuthnot Latham & Co Ltd
AER | Gross 3.40% | 3.35%
Term Instant Access
Min. Deposit £1,000
Max. Deposit £150,000
Bank name RateSetter - Part of Metro Bank
AER | Gross 3.25% | 3.20%
Term Instant Access
Min. Deposit £1,000
Max. Deposit £120,000

Already saving with us? Open your Cash ISA in seconds.

 

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Why open an Instant Access Cash ISA with Flagstone?

Convenient

Open tax-free accounts with multiple banks in one ISA.

Flexible

This is a flexible ISA, so you can withdraw as much as you like without affecting your allowance.

Rewarding

Enjoy exclusive rates and strong returns.

Practical

Transfer your existing ISAs to Flagstone for free, and stop the sprawl for good. 

How does a Cash ISA work with Flagstone?

Any money you pay into your ISA wrapper counts towards your
annual ISA allowance.  

×

Use this to fund your ISA holding account.

1 / 3

Your nominated UK current account

Fund

Withdraw

ISA wrapper

×

This acts as a temporary home for your funds while you choose which tax-free accounts to open.

2 / 3

Your Flagstone ISA holding account

Deposit

Return

×

Deposit into as many accounts as you like from multiple banks. When your accounts mature, use the funds to open new accounts, or withdraw to your nominated account. 

3 / 3

Earning interest

Tax-free account

Tax-free account

Tax-free account

Tax-free account

How does the Instant Access Cash ISA compare?

Bring your cash together. No more scattered Cash ISAs.

Flagstone Cash ISA

Manage multiple tax-free accounts in one platform

Make unlimited deposits and withdrawals within your ISA limit

Switch to higher rates with ease

Traditional Cash ISAs

A different login for every ISA

Potential hidden penalties for withdrawals

Moving cash means more applications

How Flagstone

makes money

For each account you open with our bank partners through Flagstone, we receive a small share of the interest. We deduct that share before we feature any account in our platform – so the rate you see will always be the rate you receive.  

We don’t charge admin, management, or platform fees.  

 

This is how our share of the interest works →

End ISA admin with Flagstone

 

Manage multiple tax-free accounts in one platform, and move money effortlessly to secure better rates.

 

SEE ALL RATES

Unlock earnings with our partners 

Open multiple tax-free accounts from our trusted bank partners. 

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What is an Instant Access Cash ISA?

Instant Access Cash ISAs are accounts that allow you to earn tax-free savings interest from available banks.

The term 'Instant Access' describes how you can withdraw your savings. There are no penalties for making withdrawals.

At Flagstone, you open a Cash ISA, then choose what to hold inside it: Instant Access accounts, Fixed Rate accounts, or a mix of both. There's no separate application process once your Flagstone Cash ISA is up and running.

Is an Instant Access Cash ISA the same as an Easy Access Cash ISA?

Yes. ‘Instant Access’ and ‘Easy Access’ Cash ISAs are the same thing. Both terms refer to Individual Savings Accounts (ISAs) offering immediate withdrawals to your holding account.

Can you take money out of an Instant Access ISA?

Yes. You can withdraw money whenever you like from a tax-free Instant Access account without a penalty.

By contrast, Fixed Rate accounts lock your money away for an agreed period. So, you may need to pay an early withdrawal charge if you want access to your money before the term ends.

How many times can I withdraw from an Instant Access Cash ISA?

The Flagstone Cash ISA is flexible. So, you can withdraw as often as you like from Instant Access accounts within the Flagstone Cash ISA, without affecting your annual ISA allowance.

What is a flexible Cash ISA, and can I replace what I withdraw?

Flexible Cash ISAs let you withdraw and redeposit your money as many times as you like without affecting your overall £20,000 annual limit.

The Flagstone Cash ISA is flexible.

Can I transfer an existing Cash ISA to Flagstone?

Yes. You can ask Flagstone to request the transfer on your behalf.

If you withdraw your Cash ISA funds yourself, HMRC will register the transfer as a new contribution – meaning you may use up your annual allowance.

Can I hold an Instant Access and a Fixed Rate Cash ISA at the same time?

Yes. Flagstone makes it simple to manage multiple Instant Access and Fixed Rate tax-free accounts in one platform, in one place.

How often is interest paid on an Instant Access Cash ISA?

Interest is applied to your account either daily or monthly, depending on the rules of the tax-free accounts you choose to open.

Interest is paid to you when you close the account.

How will the 2027 ISA allowance changes affect me?

From 06 April 2027, the Cash ISA contribution limit will reduce to £12,000 for most savers. If you’re aged 65 or over, you can continue to fund Cash ISAs up to the full £20,000 annual allowance.

How quickly can I withdraw my funds from an Instant Access Cash ISA?

Tax-free Instant Access accounts require no notice period and will not charge you for making withdrawals. But ‘Instant Access’ does not mean that funds appear in your holding account immediately. Transfers can take as much as 48 hours to complete.

This ensures banks can make essential security checks to keep your money safe.

Withdrawal times can vary depending on partner banks.

What is the minimum deposit to open an Instant Access Cash ISA?

The minimum deposit required to join Flagstone is £10,000.

Once you've been successfully onboarded onto the platform, you can open savings accounts as well as the Flagstone Cash ISA, which holds the tax-free Instant Access accounts.

We have to keep your savings accounts and the Flagstone Cash ISA separate on our platform for tax and reporting reasons.

Through our platform, you can spread your funds across multiple banks to help maximise growth.

Are my deposits FSCS protected in Instant Access Cash ISAs with Flagstone?

Yes. Provided your deposits are eligible, they're protected up to £120,000 per client, per banking group. This includes deposits made in Instant Access accounts within the Flagstone Cash ISA.

Evolve your savings style

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We’re at your service

Still need answers? Whether you’ve opened your Flagstone account or you’re just getting started, we’re here to help.

Call us on +44 (0)203 745 8130, Monday-Friday 9am-5.30pm.

 

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