Tax treatment
Why the coupon-to-gain split matters
Suppose two investments offer a similar pre-tax return. A savings account pays almost all of it as taxable interest. A low-coupon conventional gilt bought below £100 may deliver a small taxable coupon and a larger gain when it is redeemed at £100. For a UK individual, that qualifying gilt gain is generally exempt from Capital Gains Tax.
Coupon
The fixed annual payment per £100 nominal. Conventional gilts normally pay it in two equal instalments. Outside a wrapper, it is savings income.
Discount to par
If the clean purchase price is below £100, the movement to the £100 redemption value can create a gain. For qualifying direct gilts, that gain is CGT-exempt.
Total yield
Coupon plus the price change, adjusted for time, accrued interest and costs. This—not the coupon—is the proper starting point for comparison.
Current UK rates to keep straight
For 2026/27, savings income rates are 20%, 40% and 45%. From 6 April 2027, enacted savings rates rise to 22%, 42% and 47%. The Personal Savings Allowance remains £1,000 for basic-rate taxpayers, £500 for higher-rate taxpayers and £0 for additional-rate taxpayers. A separate starting rate for savings can apply where other income is low.
The limitations are material. The direct-gilt exemption is not a blanket exemption for bond funds or ETFs. The Accrued Income Scheme can affect taxable interest when a security is bought or sold between coupon dates. Companies, trusts, non-UK residents and people using specialist securities can face different rules. Inside an ISA or SIPP, the low-coupon tax split is largely irrelevant because the wrapper shelters both income and gains.
The mechanics
What a gilt is and what you own
A gilt is a sterling liability issued by HM Treasury and listed on the London Stock Exchange. With a conventional gilt, the government promises a fixed coupon every six months and repayment of £100 for each £100 nominal at maturity. The market price can be above or below £100 before then.
Conventional gilt
Fixed cash coupons and a fixed £100 nominal redemption value. This is the type most relevant to the low-coupon tax strategy.
Index-linked gilt
Coupons and principal move with RPI under either a three-month or legacy eight-month indexation lag. A low stated real coupon is not directly comparable with a low coupon on a conventional gilt.
Clean and dirty price
Market tables usually show a clean price. The amount paid is the dirty price: clean price plus accrued interest, before fees. Compare on the cash price you will actually pay.
Yield to maturity
The annualised return implied by price, coupons and redemption if held to maturity and paid as promised. Quoted yields still depend on conventions and reinvestment assumptions.
Price and yield move in opposite directions. If market yields rise, the fixed payments from an existing gilt become less attractive and its price falls. If yields fall, its price rises. As a conventional gilt approaches maturity, its price tends towards £100, provided the promised payments remain credible.
Market behaviour
How gilts can react across the cycle
There is no single “gilt trade”. Short and long maturities can behave very differently because the yield curve reflects expected Bank Rate, inflation, growth, government borrowing, supply and the term premium investors demand for locking money away.
| Environment | Typical yield pressure | Likely price effect | Where risk concentrates |
|---|---|---|---|
| Inflation surprise or tighter policy | Up | Prices usually fall | Long, low-coupon gilts can fall much more because their duration is high. |
| Disinflation or expected rate cuts | Down | Prices usually rise | Long gilts often gain more, but the move may already be priced in. |
| Growth shock or recession | Often down | Gilts may rally | Not guaranteed if inflation, currency or fiscal concerns dominate. |
| Fiscal or term-premium shock | Long yields up | Long-gilt prices fall | The long end can sell off even without an immediate Bank Rate change. |
| Approaching maturity | Less influential | Price converges towards par | Rate sensitivity falls, but reinvestment risk rises as cash is returned. |
Duration rule of thumb: a gilt with modified duration of 12 could lose roughly 12% if its yield rose by one percentage point, before allowing for convexity. Maturity is only a rough proxy; low coupons and longer maturities generally increase duration.
Before buying
The risks the tax story can hide
- Duration mismatch.A long gilt is not a cash substitute. Its quoted price can move violently even though the £100 redemption value is fixed.
- Forced-sale risk.The hold-to-maturity case only works if your cash need matches the maturity date and you are able to wait.
- Inflation risk.A fixed nominal repayment can lose purchasing power. Index-linked gilts address a different problem and have their own real-yield risk.
- Price and dealing friction.Delayed mid-prices are not executable. Bid-offer spreads, accrued interest, platform fees and minimum dealing charges reduce the return.
- Tax over-simplification.Coupon timing, allowances, the Accrued Income Scheme and a change in your marginal tax rate can alter the result.
- Opportunity and reinvestment risk.Yields can rise after you buy, while a maturing short gilt may return cash when replacement yields are lower.
A disciplined way to use the screener
- Start with the date when the money is genuinely needed.
- Filter conventional gilts around that maturity, not simply the lowest coupon.
- Obtain an executable clean price, accrued interest and all dealing costs.
- Compare gross redemption yield and after-tax return with cash, money-market funds and other gilts.
- Stress-test an early sale and a one-percentage-point rise in yields.
Common questions
Low coupon gilts FAQ
Are UK gilts tax-free?
Not entirely. For an individual, gains on qualifying gilts are generally exempt from UK Capital Gains Tax, but conventional gilt coupons are taxable savings income when held outside an ISA or pension. Personal allowances and residence can change the result.
Why can a low-coupon gilt be tax-efficient?
If a conventional gilt is bought below its £100 redemption value, part of the return may arrive as a price-to-par gain rather than coupon income. The coupon is taxable, while the qualifying gilt gain is generally exempt from Capital Gains Tax. A low coupon alone does not guarantee a good after-tax return.
Does low coupon mean low yield?
No. Coupon is the fixed annual cash payment based on £100 nominal. Yield reflects the price paid, coupons, time to maturity and redemption value. A low-coupon gilt trading well below par can have a market yield similar to a higher-coupon gilt.
Are short-dated gilts risk-free?
No. Short-dated gilts usually have less interest-rate sensitivity than long gilts, but their market value can still move. You also face inflation, reinvestment, dealing-cost, liquidity, tax and opportunity-cost risks, particularly if you sell before maturity.
Do gilt funds and ETFs receive the same CGT exemption?
Do not assume so. The direct-gilt exemption applies to qualifying gilt-edged securities. A fund or ETF is a separate investment whose distributions and gains follow fund tax rules, even when its portfolio holds gilts.
Is a low-coupon gilt still useful inside an ISA or SIPP?
The special split between taxable coupon and CGT-exempt gain matters less inside a tax wrapper because both income and gains are sheltered. Inside a wrapper, compare yield, maturity, duration, inflation exposure, costs and liquidity rather than choosing on coupon alone.
Sources and maintenance
Official data, explicit cut-off
The table contains all gilts reported in issue by the UK Debt Management Office at close of business 21 August 2026. It includes names, ISINs, coupons, issue and redemption dates, coupon dates and amounts outstanding. It does not claim to provide live, bid, offer or executable prices.