Best Cash ISA Providers UK 2025: Expert Comparison
We’ve reviewed the best cash ISA providers in the UK for 2025, so you can make an informed choice.
Published:
When you purchase through links on our site, we may earn an affiliate commission. Here's how it works.
Tired of watching taxes eat away at your hard-earned savings? A cash ISA (individual savings account) can let you save up to £20,000 each year without paying a penny in tax on the interest you earn. It’s a smart, tax-efficient way to grow your savings and keep more of your money where it belongs: in your pocket.
However, with so many providers out there, choosing the best option can be tough. To make your decision easier, we've researched and compared the top 5 cash ISA providers in the UK for 2025 based on factors like interest rates, accessibility, user tools, minimum deposit requirements and flexibility.
Whether you’re looking for the best instant cash ISA for flexible access, the best 1-year fixed ISA for short-term savings, or the best 2-year or 3-year fixed ISA for long-term growth, use this guide to find the right provider for your needs.
5 best cash ISA providers in 2025 compared
Let's compare 5 of the best cash ISA providers in the UK so you can pick one that meets your needs.
Provider | Best for | Our expert score | Minimum deposit | Interest rate | Access type | Fee | FSCS* protection? |
Moneybox | Tech-savvy savers | 4.7/5 | £500 | 4.78% (first 12 months) | App only | None | Yes |
Post Office | Hybrid banking (in-person and digital) | 4.6/5 | £500 | Varies | Online/Branch | None | Yes |
Plum | Low minimum deposit | 4.6/5 | £1 | 4.76% (first 12 months) | App only | None | Yes |
Hargreaves Lansdown | Accessing multiple ISA providers in one place | 4.7/5 | Varies by provider | Varies by provider | Online | None | Yes |
Kent Reliance | Reliability and flexibility | 4.4/5 | £1,000 | Varies by type | Online/Branch | None | Yes |
*The Financial Services Compensation Scheme (FSCS) is a UK statutory scheme that protects customers of failed financial services firms, such as banks or building societies. It safeguards money held in various products, including cash ISAs, current accounts, and savings accounts for up to £85,000, per person, per provider.
1. Moneybox – Best for tech-savvy savers
Our expert score: 4.7/5
Pros
- No platform fee
- Withdraw up to 3 times per year with no impact on your rate
- Easy online account opening and management
- FSCS insured account
Cons
- Requires a minimum balance of £500 to earn the best rates
- No fixed-rate ISAs
Moneybox is a digital-first savings and investment platform designed for tech-savvy users. It offers a competitive cash ISA with a variable Annual Equivalent Rate (AER) of up to 4.78% for the first 12 months. This is one of the best easy-access ISA rates we’ve seen.
After the 12-month bonus period, the rate drops to 4.20% AER (variable). The account allows up to 3 withdrawals per year without impacting your rate. You’ll need to keep your balance above £500 to get the best rate, however. Otherwise, the rate drops to 0.75% variable.
Moneybox’s cash ISA is entirely managed through its user-friendly mobile app, where you can easily open accounts, manage contributions, and transfer ISAs from other providers.
Why buy? Expert verdict
Moneybox’s cash ISA is an excellent choice for savers who prefer a digital-first approach to managing their finances. Its user-friendly app makes it easy to monitor and manage your savings. You can easily open accounts, manage contributions, and transfer ISAs from other providers. Additionally, you can make up to 3 penalty-free withdrawals per year, adding an extra layer of flexibility that many competitors lack.
Overall, if you're looking for a straightforward, high-yield cash ISA with great flexibility, Moneybox is a top contender.
2. Post Office – Best for in-person and digital banking
Our expert score: 4.6/5
Pros
- Multiple ISA options, including easy-access and fixed-rate cash ISAs
- No platform fee
- Open online, by phone, or in-branch
- FSCS insured account
Cons
- Fixed-rate cash ISAs require a minimum deposit of £500
Post Office customers can choose between an easy-access ISA, which comes with variable rates and allows withdrawals without penalty, or a fixed-rate ISA, which offers a stable, guaranteed, and often higher rate in exchange for a long-term lock-in.
For those who prefer a fully digital experience, the Post Office also offers an online cash ISA. This option allows you to seamlessly switch between easy-access and fixed-rate features within the same account.
Why buy? Expert verdict
Post Office has a legacy that dates back to 1861 when it first started offering banking products. It’s an excellent choice for savers who value a trusted, experienced brand with flexible options.
Additionally, you can open these accounts online, by phone, or in-branch at the Post Office's extensive network of thousands of branches across the UK. So, if you prefer or appreciate in-person service alongside digital banking convenience, this could be a great option.
Our expert score: 4.6/5
Pros
- Mobile-first experience with an easy-to-use app
- Low minimum opening deposit of £1
- No fees for opening or managing an ISA
- FSCS insured account
Cons
- Minimum account balance of £100 for the best interest rates
Plum is a digital savings platform that offers a cash ISA with a great interest rate. For the first 12 months, you can earn up to 4.76% AER (variable), which includes a Plum bonus of 1.22% AER. Note however that you need to maintain a minimum balance of £100 and not make more than 3 withdrawals per year to enjoy this rate. Failure to meet these conditions will see your rate fall to 2.50% AER (variable).
You can easily open Plum’s cash ISA is available through its highly rated and user-friendly app. And if you already have an existing ISA with another provider, you can also easily transfer it to Plum through the app.
Why buy? Expert verdict
Plum stands out for its low barrier to entry, allowing you to open an account with as little as £1. This low minimum deposit makes Plum particularly appealing for anyone looking to build a savings habit gradually without needing a large upfront commitment.
However, to unlock the best available interest rates, you’ll need a minimum balance of £100.
✍️ Have you used this cash ISA provider? Share a rating and review for Plum on Review Centre.
4. Hargreaves Lansdown – Best for accessing multiple providers in one place
Our expert score: 4.5/5
Pros
- Several types of cash ISAs to choose from
- No platform fee
- Access to a range of competitive ISA savings rates from multiple banks
- FSCS insured account
Cons
- Some cash ISAs have relatively high minimum deposit requirements (up to £1,000)
Hargreaves Lansdown (HL) offers a unique cash ISA product that allows savers to hold and manage multiple tax-free savings products from different providers under one roof. You can transfer your savings between partner providers as your needs change or to maximise your interest rates without the hassle of opening a new account each time.
Additionally, you can invest in as many savings products as you want as long as you don’t exceed your annual £20,000 allowance.
Why buy? Expert verdict
Hargreaves Lansdown is ideal for savers who want maximum flexibility and access to a range of ISA providers including banks and building societies in one place. If you actively track interest rates, this platform allows you to take advantage of the best deals as soon as they become available, without paperwork. Simply log in to your account and switch between providers or savings products with just a few clicks.
In addition, you can start saving with as little as £1. However, some products, particularly those that offer better-than-average rates have higher minimum deposit requirements.
HL also enjoys a strong reputation for customer service and support, which further enhances its appeal.
✍️ Have you used this cash ISA provider? Share a rating and review for Hargreaves Lansdown on Review Centre.
5. Kent Reliance: Best for reliability and flexibility
Pros
- Competitive rates
- Trusted provider, part of the One Savings Bank Group
- FSCS insured account
- No platform fee
Cons
- £1,000 minimum deposit requirement
Kent Reliance is a specialist savings provider known for offering competitive interest rates across its savings products. The company, which operates both online and through a network of branches, enjoys a strong reputation in the industry as highlighted by its win for the prestigious Best Cash ISA Provider title at the 2024 YourMoney.com Awards.
Customers can choose between an easy-access ISA, with some of the market’s best variable rates, and a fixed-rate ISA that also offers competitive returns. The fixed-rate ISA is available in one or two year terms and you can choose to get your interest payments monthly or annually. Kent Reliance also runs a £1,000 monthly prize competition for customers who have balances of £100 or more in their account.
Why buy? Expert verdict
Kent Reliance’s competitive interest rates and flexible ISA options make it a strong choice for savers looking to maximize returns while maintaining some level of flexibility.
As part of OneSavings Bank, which is known for its strong financial stability and customer focus, Kent Reliance also offers the reassurance of a well-established institution with strong financial backing. Additionally, the 14-day cooling-off period for its fixed-rate ISAs offers a safety net not commonly found with other providers.
✍️ Have you used this cash ISA provider? Share a rating and review for Kent Reliance on Review Centre.
Types of Cash ISAs
Here are the main types of cash ISAs:
Easy-access ISAs
Also known as instant-access ISAs, these allow you to deposit and withdraw funds without penalties. Easy-access ISAs have variable interest rates, meaning the rate you earn on your savings can fluctuate and change over time, depending on economic factors.
Fixed-rate cash ISA
Fixed-rate cash ISAs offer a fixed rate in exchange for locking your cash away for a set period (usually 1-5 years). That means that even if market rates go down, your rate won’t be affected. You may face a penalty if you withdraw your cash early or even lose your interest.
Notice-cash ISAs
With these ISAs, you can withdraw without penalty as long as you provide a certain number of days’ notice (e.g., 15, 30, or 60 days, depending on the provider). While you might be able to take out cash within the notice period, you'll likely incur a penalty.
Junior cash ISAs (JISAs)
Designed for children under 18, junior cash ISAs allow parents or guardians to save on behalf of their child. The funds are locked until the child turns 18, at which point they gain full access to the account. A JISA is the best tax-free cash ISA to build a savings pot for a child’s future.
Cash lifetime ISAs
Lifetime ISAs, or simply LISAs, are designed to help you save for your first home or retirement. You can keep cash, or stocks and shares in them or have a combination of both. The government adds a 25% bonus to your contributions, up to £1,000 per year. However, withdrawals before age 60 (except for a first home purchase) incur a penalty.
What type of cash ISA do I need?
The right cash ISA type for you depends on your savings goals, financial habits, and the amount of flexibility you desire. Here are some key factors to consider:
- Access to your money: If you need flexibility to withdraw funds at any time, an easy-access cash ISA is your best option. For long-term savings where access isn’t a priority, a fixed-rate ISA could be more suitable.
- Savings goals: Easy-access and notice ISAs work well for short-term needs, like setting up an emergency fund. Meanwhile, fixed-rate and lifetime cash ISAs are better for long-term goals, such as a first home, retirement, or your child's future financial security.
- Interest rates: For higher interest rates, you might want to consider a fixed-rate cash ISA. Those looking for flexible access to their funds can choose the lower-rate instant access ISA. Compare rates across providers and account types to maximise your returns.
- Minimum deposit requirements: Some cash ISAs may require a minimum deposit to open the account or to qualify for the best interest rates. Ensure you check the terms and conditions to see if the account aligns with your initial savings amount.
- Financial protection (FSCS): Make sure the provider you choose is covered by the Financial Services Compensation Scheme (FSCS). This safeguard makes sure your cash is secure even if the bank or building society experiences financial difficulties.
How cash ISAs work
Cash ISAs function as tax-free savings accounts, allowing you to grow your money without paying tax on the interest earned. Here’s everything you need to know about how they work.
Who can open a cash ISA?
To open a cash ISA, you must be a UK resident or a Crown employee, member of the armed services, or their spouse. Further, you must be at least 18 (and under 40 for a lifetime cash ISA). However, due to a policy change, if you were born between 6 April 2006 and 5 April 2008, some providers will let you open one cash ISA before you turn 18.
Parents or guardians can also open a Junior Cash ISA for children under 18. The child gains control of the account when they turn 16 but cannot withdraw funds until they are 18.
What’s the maximum amount you can put in a cash ISA?
For the 2024/25 tax year, the annual ISA allowance is £20,000. You can put all of this in your cash ISA(s), or you can spread it between different ISA types, such as a stocks and shares ISA and innovative finance ISA.
Benefits of a cash ISA
The primary benefit of a cash ISA is that you don't pay income tax on the interest earned. Plus, it's a safer and less volatile way to grow your savings compared to investing it in stocks, shares, and other assets impacted by market fluctuations. Also, depending on the type of cash ISA, you can withdraw funds when needed—often without a penalty.
How to open and manage a cash ISA
Opening a cash ISA is straightforward. You can do it through banks, building societies, credit unions, or online financial services providers. Here's how:
- Choose an ISA type: Decide which type of cash ISA you want, e.g., easy-access, fixed-rate, notice ISA, etc.
- Select a provider: Compare interest rates, fees, and customer reviews to find the best option.
- Apply: Most providers allow you to open an account online or by phone, though some may require branch visits. As part of your application, you’ll need to provide documents, such as proof of your identity (passport or driver’s licence) and address.
- Fund your account with the minimum requirement: You can make deposits via bank transfer, cheque, or cash (depending on the provider).
Once your account is open, you can typically manage it online or through your provider’s app. If you want to switch providers for better rates, ensure you do this via an official ISA transfer request. Otherwise, you will lose the tax-free status of the withdrawn amount even if you immediately invest in another ISA — that is, it will count again towards your annual £20,000 limit.
Who are the biggest cash ISA providers in the UK?
Here are some of the biggest and most well-known cash ISA providers in the UK for 2025:
- Barclays
- Post Office
- Nationwide Building Society
- Yorkshire Building Society
- HSBC
- NatWest
- Plum
- Moneybox
- Marcus by Goldman Sachs
- Kent Reliance
- Plum
- Hargreaves Lansdown
These providers are recognised for their strong financial stability and commitment to customer satisfaction, making them top choices for those looking to invest in a cash ISA in 2025.
How to choose the best cash ISAs
Consider the below factors to ensure you pick the best cash ISA for your needs.
Interest rates
Compare the interest rates offered by different providers. Make sure you're getting a competitive rate for the type of ISA you're interested in.
Fees and penalties
Carefully read the terms and conditions to identify any fees for withdrawals, transfers, or account maintenance. Avoid providers with excessive charges that could eat into your savings. Additionally, ensure you understand the penalties for early withdrawals.
Customer service
Evaluate the provider’s customer service options, such as phone, email, live chat, or in-branch support. Test their responsiveness by reaching out with questions before you open an account. A provider with responsive, helpful customer service can make your savings experience much smoother.
Provider reputation
Read customer reviews, ratings, and testimonials on websites like Review Centre to gauge the provider’s reliability. Look for providers with a strong track record and positive feedback from savers.
Digital tools
If online banking is important to you, explore the provider’s website or mobile app. Ensure the platform is user-friendly, secure, and offers important features like balance checks, transfers, and account management.
Additional features
Check if the provider offers extra perks, such as linked savings accounts, bonus interest rates, or financial planning tools. These features can add value to your savings journey.
Provider’s financial stability
Research the provider’s financial health by reviewing their annual reports or checking credit ratings from agencies like Moody’s or Standard & Poor’s. A financially stable provider is less likely to cut rates abruptly or face operational issues that could affect your savings.
How we created this list
We carefully evaluated each provider's offerings, performance, and reputation on the following factors:
- Competitive and attractive interest rates.
- Ease of access and flexibility to manage funds, with particular attention to withdrawal terms, transfer policies, and overall flexibility.
- Fees and charges, including any associated fees, minimum deposit requirements, and account management charges.
- Provider reputation, including their history, financial stability, customer reviews, customer support, and industry awards.
- Types of cash ISAs offered, including any access, fixed-rate, notice, and junior ISAs, to ensure that customers have a range of options for different savings goals.
- Access to online platforms and secure mobile apps with features that are useful to savers.
Cash ISA FAQs
Can you open multiple cash ISAs with different providers?
Yes. As of April 2024, you can open multiple cash ISAs, either with one provider or multiple providers in the same tax year. You can contribute to all your cash ISAs as long as you don't exceed your annual ISA allowance, which is £20,000 as of 2025.
Can I lose money in a cash ISA?
You cannot lose your initial deposit in a cash ISA, as it’s a savings account. Additionally, deposits in cash ISAs provided via authorised banks or building societies in the UK enjoy FSCS protection of up to £85,000 per eligible person, per provider.
That said, if interest rates are lower than inflation, the value of your savings in a cash ISA could decrease over time. Also, withdrawing money early from a fixed ISA could lead to penalties, such as several months' interest depending on the terms of your provider.
What happens if I exceed my ISA allowance?
If you accidentally exceed the annual ISA allowance (£20,000 for 2024/25), contact HMRC through its official ISA helpline. HMRC will work with your provider to refund the excess payment. However, you may have to pay tax on any growth or interest generated by the excess funds.
What are the negatives of a cash ISA, if any?
While cash ISAs offer tax-free interest, they may offer lower returns than other investment options like stocks and shares ISAs, depending on market conditions. Some accounts may also have withdrawal restrictions, penalties for early access, or require a minimum deposit. Furthermore, if interest rates are low, the returns may not keep up with inflation.
Conclusion
A cash ISA provides a secure and tax-efficient way to grow your savings. Choosing the right cash ISA type and provider is key to maximising your returns and ensuring flexibility that suits your financial needs.
Our review of the best cash ISA providers should give you plenty of insights to help you pick the right provider and start saving today.