The cash that leaves your account on a gilt trade is the dirty price for the nominal you bought, plus any dealing cost, and it is worked from the clean price and the accrued interest to the settlement date.
Settlement is when the cash moves
The figure that matters on a gilt purchase is the one on the settlement date, because that is when the cash actually leaves your account. It is built from three parts: the clean price for the nominal you bought, the accrued interest to the settlement date, and any dealing cost your provider charged. Reading a contract note means reconciling those three against the gilt's row.
The clean price and the accrued interest are what the gilt costs; the dealing cost is what the dealing costs. Keeping the two ideas apart — the price of the thing and the charge for buying it — is what makes a settlement figure checkable rather than a single number to accept.
Accrued interest is counted to the settlement date rather than the day you placed the order, so a settlement date a day or two later adds a day or two of interest. The site resolves a booked trade to a settlement date from the delay on your profile — T+1 or T+2 — and measures the accrued interest to that date. It is the settlement, not the click, that sets the number.
That is why a quote given on the dealing day is close to, but rarely identical with, the cash that settles. The small difference is the interest that accrued in the days between.
An illustrative settlement
The table works one purchase through the parts; the figures are illustrative, every input is stated, and none of them is a current price. Take a clean price of 99.20, a half-yearly coupon of 2.25 on a 182-day period with 60 days accrued to settlement, and a nominal of £2,000 (twenty units).
| Line | Working | Amount |
| Clean price | 20 × £99.20 | £1,984.00 |
| Accrued interest | 20 × (2.25 × 60 ÷ 182) | About £14.84 |
| Dirty price (cash) | £1,984.00 + £14.84 | About £1,998.84 |
| Dealing cost | The provider's stated fee | Separate, per the provider |
The clean price and the accrued interest add up to the dirty price, and the dirty price times the nominal is the cash before any dealing cost. A line that does not reconcile is usually a day-count or settlement-date difference rather than a mistake in the price.
The dealing cost is shown separately because it is not part of the price: it does not change the clean or the dirty figure, it is added to the cash at the end. A reader comparing two accounts is comparing that line, not the price of the gilt, which is the market's for both.
Index-linked gilts scale the dirty price
An index-linked gilt adds one more factor: the index ratio, which scales both the coupon and the redemption for the rise in prices since issue. The dirty price is the clean price plus accrued interest, then multiplied by the index ratio, so the cash is higher than the same clean price would give on a conventional gilt. The gilt's own page, opened from the conventional gilts list, shows every future coupon and the final repayment on its per-£100 cash-flow schedule, scaled the same way, so the cost can be set against what comes back.
Checking it against the record
The record-a-trade form takes the clean price and the accrued interest and derives the dirty price, and the trades ledger keeps the settlement date and the fees with the booking. Reconciling the contract note to those figures — clean plus accrued equals dirty, and dirty times nominal plus fees equals cash — is how a settlement figure is checked rather than trusted.
That reconciliation is what makes the settlement figure a measurement rather than a claim. If the clean and the accrued do not add to the dirty, no amount of trusting the total will fix it; the three lines have to agree.
Why the dealing cost sits outside the dirty price
The dirty price is a price for the gilt; the dealing cost is a charge for the dealing. Keeping them apart is what lets a reader see both — what the gilt cost at the market's price and what the route added. A contract note that folds a commission into the price hides one of the two, which is why GiltIQ records the fees as their own figure per booking rather than adjusting the dirty price.
The separation also matters for a report. A portfolio valued from the market price reflects the gilt, not the cost of buying it; a taxable income report works from the coupon and the accrued interest, not the dealing cost. Both use the price, and the fees sit beside it as a separate, stated amount.
A quick check on any settlement
Any settlement can be checked in a few lines without a calculator. Convert the clean price and the accrued interest to pounds for the nominal held, add them for the dirty cash, and add any dealing cost at the end. If the three prices on the note do not add up — clean plus accrued equals dirty — the difference is almost always the accrued days rather than the price.
Running the check against the gilt's row, not only against the note, closes the loop. The row gives the clean price and accrued interest the site reads from the report; the note gives what was charged; and where they differ, the settlement date is the first thing to compare.
Background, not advice
This guide explains how the cash on a gilt settlement is worked out; it is general background, not investment, tax or legal advice for any reader's circumstances. Every figure above is illustrative and states its inputs, and a contract note and the gilt's own record are the primary sources for a real settlement.