Premium Bonds vs Savings After-Tax Calculator (UK, 2026)

The Premium Bonds headline prize rate (4.40%) is the mean of a skewed prize distribution — most small-to-medium holders earn below the median. This tool computes both expected and median Premium Bonds return, then compares against easy-access and fixed-rate savings after Income Tax and Personal Savings Allowance. For higher-rate taxpayers with £20k+ holdings, Premium Bonds usually win — but this shows when they don’t.

⏱️ 3-5 minutes • 💪 Quick

How This Tool Works

📋 Purpose

The headline Premium Bonds prize rate of 4.40% looks competitive — but it\'s the MEAN of a skewed prize distribution, and the MEDIAN holder earns less. Meanwhile savings interest is taxed at 20-45%. This tool computes both expected and median Premium Bonds returns, then compares against easy-access and fixed savings after Income Tax and Personal Savings Allowance.

⚙️ How It Works

  1. 1
    Enter your Premium Bonds holding amount.
  2. 2
    Specify your holding period in months.
  3. 3
    Select your UK tax band.
  4. 4
    Input PSA already used this tax year.
  5. 5
    Set comparison easy-access and fixed-rate APRs.
  6. 6
    We calculate expected and median Premium Bonds return.
  7. 7
    We apply your PSA and tax band to savings.
  8. 8
    We recommend the winner for your situation.

Recommended Cost Saver Partner

Sponsored Partner Alert

Take control of your net pay and investments. Build your financial freedom strategy with Moola Pro.

We may earn a commission on purchases at no extra cost to you. While we only partner with trusted platforms through reputable affiliate networks, all services and accounts are managed directly by the provider, who will handle any customer care or account needs.

Premium Bonds vs savings — UK, 2026

Premium Bonds pay 4.4% tax-free — but is that really better than a 4.8% fixed bond after tax?

Compare NS&I Premium Bonds expected return against easy-access and fixed-rate savings on a properly after-tax basis. For higher-rate taxpayers and £20k+ holdings the calculation often flips in Premium Bonds’ favour — but not always. This tool shows you which.

Your holding

Minimum £25, maximum £50,000.

Interest already earned on other accounts this tax year.

Used to show real purchasing power. ONS CPIH ~2.5% (Apr 2025).

Comparison rates and preferences

NS&I default. Keeps compounding.

Recommended Cost Saver Partner

Sponsored Partner Alert

Don't leave your salary to chance. Optimize your investments and reach financial freedom with Moola Pro.

We may earn a commission on purchases at no extra cost to you. While we only partner with trusted platforms through reputable affiliate networks, all services and accounts are managed directly by the provider, who will handle any customer care or account needs.

Was this tool helpful?

Your quick feedback helps improve our tools

Complete Guide: Premium Bonds vs UK Savings After Tax (2026)

Understand when NS&I Premium Bonds beat regular savings — and when they don’t.

📅 Last updated: April 2026

Quick Tips

Jump-start your understanding with these essential tips

With PSA exhausted, every £1 of savings interest is taxed 40%+. Premium Bonds’ tax-free 4.40% beats a taxable 5% easily.

The £1,000 PSA means you can earn £1,000 tax-free in a regular savings account — often better than Premium Bonds expected median.

Under £1,000 you have a very high chance of winning zero in any 12-month period. The headline 4.40% is the AVERAGE — not what most small holders actually get.

Cash ISAs give £20k/year tax-free capacity — mathematically better than Premium Bonds for most people until ISA is full.

Monthly excitement and lottery optionality encourage consistent saving. If Premium Bonds keep you saving more than a dull savings account would, the "worse" expected return is easily outweighed by the higher total balance.

Step-by-Step Guide

Follow these steps to get the most from this tool

£25 minimum, £50,000 maximum.

Shorter periods have much higher variance.

Basic (20%), higher (40%), additional (45%).

Sum of savings interest earned elsewhere this tax year.

Check MoneyFacts or MoneySavingExpert for current best-buys.

See expected/median Premium Bonds vs after-tax easy-access and fixed.

Advanced Topics

Deep dives for advanced users

Premium Bonds return is the expected value of a highly skewed prize distribution. About 75-80% of holders with under £5,000 earn BELOW the 4.40% headline in any given year. The median is consistently 20-40% below the mean. For fair comparison, use the median figure unless you're comfortable with variance.

Savings interest is taxed in the year it's credited. If you buy a 2-year fixed bond that pays annually, the interest is taxable when paid (not when it accrues). Some fixed-rate accounts offer monthly interest — shifts the tax timing. Premium Bonds are tax-free regardless of prize month.

Basic-rate taxpayers: £1,000 of savings interest is tax-free via the Personal Savings Allowance. Beyond £1,000, you pay 20%. So at £20k holding + 4.5% rate = £900 interest, you're ENTIRELY within PSA and savings beat Premium Bonds decisively. At £50k + 4.5% = £2,250 interest, only £1,000 is tax-free — making Premium Bonds more competitive.

NS&I also offers Green Savings Bonds, Guaranteed Growth Bonds, and Direct Saver — all backed by HM Treasury but taxable. These usually pay less than the market best-buys. If you want HMT-backing specifically, Premium Bonds are typically the best NS&I product for higher-rate taxpayers.

Compare with ISA vs GIA for investing, Annuity vs Drawdown for retirement.

📚Read More Articles

Discover helpful guides and insights

Frequently Asked Questions

Reviewed by Asad MujtabaLast reviewed: April 2026Tool outputs can refresh continuously from live APIs where available.