What is a Cash ISA in the UK?

A Cash ISA (Individual Savings Account) is a tax-free savings account available to UK residents. You can save up to £20,000 per tax year, and all interest earned is completely tax-free. Unlike regular savings accounts, you don't pay Income Tax on ISA interest. Cash ISAs are offered by banks and building societies.

What are current Cash ISA rates in the UK?

Current UK Cash ISA rates (2026): Easy-access: 3.5-4.5%, Fixed rate (1-year): 4.5-5.0%, Fixed rate (2-year): 4.0-4.8%, Fixed rate (5-year): 3.5-4.5%. Regular saver ISAs: 5-6%. Rates vary by provider. Use this calculator to compare returns.

How much can I put in a Cash ISA in the UK?

The annual ISA allowance for 2026 is £20,000. You can put this in a Cash ISA, Stocks & Shares ISA, or split between them. You can only pay into one Cash ISA per tax year, but you can open a new one each year. The allowance resets each tax year (April 6th).

Is Cash ISA interest tax-free?

Yes! All interest earned on a Cash ISA is completely tax-free. You don't need to declare ISA interest on your Self Assessment tax return. This makes Cash ISAs more attractive than regular savings accounts, where basic rate taxpayers pay 20% tax on interest above their Personal Savings Allowance.

Cash ISA Calculator UK - Tax-Free Savings Growth Estimator

ISA Type	Rate	£10k + £200/month	5-Year Return
Easy-Access	4.0%	£24,200	£4,200
1-Year Fixed	4.8%	£24,800	£4,800
2-Year Fixed	4.5%	£24,500	£4,500
5-Year Fixed	4.2%	£24,200	£4,200
Regular Saver	5.5%	£25,500	£5,500

📝 Complete Guide to Cash ISAs in the UK

This cash ISA calculator UK helps you estimate tax-free savings growth. Cash ISAs are one of the most popular savings vehicles in the UK, offering tax-free interest on your savings.

💰 What is a Cash ISA?

A Cash ISA is a tax-free savings account available to UK residents:

Tax-Free: All interest is tax-free
Annual Allowance: £20,000 per tax year
Flexible: Withdraw and replace within same tax year
FSCS Protected: Up to £85,000 per institution
Types: Easy-access, fixed rate, regular saver

📊 Current UK Cash ISA Rates (2026)

Easy-Access: 3.5-4.5%
1-Year Fixed: 4.5-5.0%
2-Year Fixed: 4.0-4.8%
5-Year Fixed: 3.5-4.5%
Regular Saver: 5-6% (limited deposits)
Lifetime ISA: 4.0-4.5% (25% bonus)

📈 UK ISA Statistics (2026)

20M+ ISA accounts in the UK
Average ISA balance: £15,000-£20,000
60% of ISA users use Cash ISAs
Total ISA savings: £700B+
Most popular: Easy-access Cash ISAs
ISA take-up: 35% of UK adults

💡 Tips for Maximizing Your Cash ISA

Use Annual Allowance: Save £20,000 each tax year
Compare Rates: Use comparison sites
Fixed vs Easy: Higher rates for fixed terms
Regular Savers: Often higher rates
Transfer ISAs: Keep tax-free status when switching
LISA Bonus: 25% bonus for first-time buyers

⚡ Cash ISA vs Regular Savings

Cash ISA: Tax-free interest
Regular Savings: Tax on interest (20-45%)
ISA Benefit: £10,000 at 4.5% over 5 years = £2,463 tax-free
Tax Savings: Basic rate saves 20%, higher rate saves 40%
Personal Savings Allowance: £1,000 basic, £500 higher

⚠️ Important Considerations

Annual Allowance: Use it or lose it
ISA Transfers: Always use official transfer process
Withdrawal Penalties: Check fixed term terms
Provider Risk: Use FSCS protected providers
Inflation: Real return = rate - inflation

Cash ISA Calculator UK

📊 Your ISA Details

📊 ISA Breakdown

📊 UK Cash ISA Rates Comparison