UK Cash ISA Tax-Free Calculator
Savings Deposits & Rate
Configure your initial principal, interest rate, and compounding intervals.
Projected Compound Growth
Principal accumulation, interest yield, and final balance.
Calculation Result
Starting principal
12 monthly deposits of $250
Your total out-of-pocket savings
Current High-Yield & Certificate of Deposit (CD) Benchmarks
Projected annual cash earnings on a $20,000 allocation.
| Institution & Account | APY / AER | Est. Annual Yield | Est. Monthly |
|---|---|---|---|
High-Yield Savings (HYSA)RecommendedTop-Tier Online Bank (US) • Liquid / No lockup | 4.6% | $920/yr | +$77/mo |
Certificate of Deposit (CD)Direct Bank 12-Month CD • 1-Year Guaranteed Term | 4.85% | $970/yr | +$81/mo |
Cash Sweep PortfolioHigh-Yield Cash Account • Same-Day Transfers | 4.45% | $890/yr | +$74/mo |
Standard Checking / SavingsTraditional Brick & Mortar • National Average | 0.01% | $2/yr | +$0/mo |
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About UK Cash ISA Tax-Free Calculator
In the United Kingdom, Individual Savings Accounts (ISAs) protect interest and dividends from HMRC income tax. ConvertSheet's Cash ISA Calculator models easy-access and fixed-rate Cash ISAs, helping UK savers forecast compounding returns within their £20,000 annual allowance without risking private banking data on external cloud servers.
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Frequently Asked Questions: UK Cash ISA Tax-Free Calculator
Clear mathematical answers to key questions, calculations, and loan parameters.
What is the UK annual ISA allowance?
The annual UK ISA allowance is £20,000 per tax year (running 6 April to 5 April), which can be distributed across Cash ISAs, Stocks & Shares ISAs, and Innovative Finance ISAs.
Is interest in a UK Cash ISA completely tax-free?
Yes. Interest earned within an ISA is completely exempt from UK income tax and capital gains tax, and does not count toward your HMRC Personal Savings Allowance (PSA).