Most Cash ISA journeys start simple: one account, one provider, one purpose. But if you have used Cash ISAs for years, that simplicity can fade. New tax years bring new accounts, and better rates bring more switching. Over time, tax-free savings can end up spread across a handful of banks, platforms, and passwords.
That structure works – until scale makes it cumbersome.
The new generation of Cash ISAs keeps the tax wrapper, while removing much of the admin. With just one ISA application, you can open multiple tax-free accounts with different banks, all sitting under the same ISA wrapper.
What is a Cash ISA?
A Cash ISA is an account that lets you earn interest without paying Income Tax on it.
Each tax year, you receive an annual ISA allowance you can use across all eligible ISA types. For the 2025/26 and 2026/27 tax years, this is £20,000. You can split it between Cash ISAs, Stocks & Shares ISAs, and other ISA types in any combination – as long as your total contributions don’t exceed £20,000.
From April 2027, most savers under 65 years old will be able to contribute up to £12,000 a year into a Cash ISA. Those aged 65 and over will still be able to use the full £20,000 allowance.
How do Cash ISAs become complicated?
Cash ISAs become complicated gradually, as new accounts are opened over the years.
You may open a new ISA each tax year, move cash when rates change, and leave older ISAs in place. Over time, this leads to numerous providers, logins, and statements, which makes it harder to see everything clearly in one place.
For many people, that means more admin, more passwords, and more time spent checking balances. It can also make it harder to spot new rates or to see whether your cash sits comfortably within FSCS protection limits.
A new way to structure a Cash ISA
The solution is simple: keep one Cash ISA wrapper, and open several accounts inside it. That’s what the new Flagstone Cash ISA offers.
You hold one tax wrapper, and within it you can open multiple tax-free accounts with different banks – all managed through one platform, under one login.
The ISA rules stay the same, but your view becomes clearer, giving you greater control over how your cash is structured.
The Flagstone Cash ISA is coming soon
Want to be the first to hear about the new Flagstone Cash ISA?
Simply click the link on our homepage, enter your details, and we’ll email you when it launches.
The benefits of a Flagstone Cash ISA
With the Flagstone Cash ISA, you hold one ISA, yet your cash can sit across several banks on a single platform. Here are the key benefits that gives you.
1. Diversification, made simple
If you hold a significant amount of cash, diversification matters.
Spreading cash across different banks and building societies can help reduce risk and keep more of your money protected under the FSCS rules. With one wrapper and multiple bank accounts in one place, diversification becomes far easier to manage.
2. Move cash in moments
Rates change, and your cash should be able to move with them.
With the Flagstone Cash ISA, your wrapper stays in place. You can move cash between banks in moments, without filling in new forms each time or starting a new application. Less repetition. More control.
3. Transfer existing ISAs, fee-free
If you already hold Cash ISAs elsewhere, you can transfer them into Flagstone and bring everything together in one place.
There are no transfer costs, and your cash keeps its tax-free status. You can move as many existing ISAs as you like, with no limit on balances. No matter how much you transfer, it won’t cost you a penny.
Once everything sits within one ISA wrapper on one platform, you get a clear view of your ISAs and can manage them with far less admin.
4. Flexible withdrawals
The Flagstone Cash ISA is flexible. You can withdraw cash and replace it within the same tax year, without reducing your ISA allowance. This gives you access, while keeping your tax wrapper intact.
How the Flagstone Cash ISA works
Our Cash ISA will let you open tax-free accounts with separate banks – all in the same ISA wrapper. So you can see your ISA savings in one place and manage everything effortlessly.
Here’s how it works:
| Step one: Open your Cash ISA |
If you’re already a Flagstone client, opening a Cash ISA takes minutes. You only need your National Insurance number. If you don’t have a Flagstone account, complete your Cash ISA application in just a few minutes. Our UK-based team are here to help with any questions you may have. |
| Step two: Transfer in |
Transfer your existing Cash ISAs, fee-free. Cash lands in a dedicated ISA holding account while you choose which accounts to open. If you’re already a client, you’ll see two holding accounts because ISA cash must stay separate from the rest of your Flagstone portfolio. This keeps your tax-free cash clearly ring-fenced. |
| Step three: Spread your cash | Allocate cash across multiple banks and accounts within your ISA wrapper. |
| Step four: Move when rates change |
Move funds to new rates as they arise. Your wrapper stays in place, so you don't start from scratch. |
Who this suits
This structure suits people who value clarity and control as balances grow. It can help if:
- you already hold several Cash ISAs
- you want a clearer view of your tax-free cash
- you're managing a significant cash event, such as a property sale
- you want to spread cash across banks without spreading admin
Who provides the Flagstone Cash ISA?
You manage your Cash ISA through the Flagstone platform. Wealth Kernel is the FCA-regulated ISA provider.
Your cash is held in trust and remains yours at all times. Flagstone only move funds at your request, on your behalf.
Your cash also stays separate from the assets of both businesses.
See your ISA savings in one place
If you’ve opened several Cash ISAs over the years, what began as a sensible savings habit may now be a scattered sprawl.
The new generation of cash ISAs brings everything back into one place – one wrapper, multiple accounts, and a clearer way to manage tax-free cash.
Get notified when the Flagstone Cash ISA launches.
