Save · Calculator 22
Compare taxable savings, a Cash ISA, Premium Bonds and a direct conventional gilt using your rates, tax position, time horizon and dealing quote.
Your figures
Copies accessible cash and estimates a savings-tax rate and remaining Personal Savings Allowance from your profile.
Your entries stay in this tab and are not sent to Money Considered. A shareable link includes only the assumptions shown in its URL.
Highest modelled annual rate
4.50%Cash ISA, on the entered rates and tax assumptions. Premium Bonds use an expected value; this is not a recommendation or guaranteed ranking.Prize simulator
£30,000 across 24 eligible monthly draws. The expected value includes very rare large prizes, so the median can be much lower.
It matures in about 1.45 years. The gilt row runs to that maturity; the other rows run for 2 years. Choose a closer maturity before comparing the net cash gains.
Each row is a standalone use of the money. “Modelled” does not mean the rate is fixed by the product.
| Option | Amount modelled | Time used | Tax | Net or expected gain | Annual rate | What can vary |
|---|---|---|---|---|---|---|
| Taxable savings | £30,000 | 2 yr | £772 | £2,159 | 3.54% | Rate, tax position, access terms |
| Cash ISA | £30,000 | 2 yr | £0 | £2,761 | 4.50% | Rate, access terms, subscription eligibility |
| Premium Bonds | £30,000 | 24 draws | £0 | £2,610 expected | 4.26% | Prizes, odds, prize-fund rate |
| 0⅛% Treasury Gilt 2028 | £30,000 | 1.45 yr | £0 | £1,783 | 4.07% | Quote, costs, accrued interest, tax, early-sale price |
£30,000 buys about £31,723 nominal at a dirty price of £94.530 per £100, after £12 dealing cost. The model adds £59 gross coupons, estimates £0 coupon tax and treats the move to £31,723 redemption value as CGT-exempt for a qualifying direct gilt held by a UK individual.
Match the product to the date the cash is needed. A long gilt is not a cash account, and a high expected Premium Bonds return can coexist with a much lower median outcome.
Common questions
No. A taxable account with a higher rate can produce more after tax where interest remains inside the Personal Savings Allowance or starting rate for savings. Compare net rates, access terms, guarantees and whether using ISA allowance now has longer-term value.
For 2026/27, the Personal Savings Allowance is up to £1,000 for a basic-rate taxpayer, £500 for a higher-rate taxpayer and £0 for an additional-rate taxpayer. The lab applies the unused amount you enter in each modelled year. Other interest and a move between tax bands can change it.
The prize-fund rate is an average used to fund the draw, not interest paid to each holder. From the September 2026 draw NS&I states a 4.35% prize-fund rate and odds of 21,000 to one per £1 Bond each month. A personal outcome can be zero or far above the average.
Rare high-value prizes lift the mathematical mean. Most wins are small and many smaller holdings win nothing over a short period, so the middle simulated outcome can be below the expected value. The lab shows both.
It uses NS&I’s estimated September 2026 number of prizes at every tier, the published odds and 10,000 deterministic simulations. It assumes a fixed holding and independent monthly chances. NS&I can change the rate, odds and prize allocation, and the simulation is not a prediction of a particular Bond number.
For a qualifying direct gilt held by a UK individual, coupon income is taxable savings income but the price gain is generally exempt from Capital Gains Tax. A low-coupon gilt bought below £100 can therefore place more return in the exempt price-to-par uplift. Price, maturity, accrued interest and dealing costs still determine the result.
Only with care. A conventional gilt held to maturity has a fixed nominal redemption amount, but its market price can move before maturity. A maturity mismatch can create forced-sale risk, and longer gilts can have substantial duration risk. The lab flags when the selected maturity differs from the cash horizon.
No. It does not check ISA subscription eligibility, the announced Cash ISA limit change from April 2027, the Financial Services Compensation Scheme limit, joint ownership or provider-specific access restrictions. Verify these separately.