Offshore Bond 5% Allowance Calculator

What this calculator does and who it's for

This tool estimates how much you can take from an offshore investment bond in a given policy year without crystallising a chargeable event gain, using the 5% cumulative withdrawal allowance that UK tax law grants to these wrappers. It is built for holders of an offshore bond — and the internationally mobile investors and returning expats who most often use them — who want a quick, defensible figure before drawing an income or a lump sum. Offshore bonds are a mainstream tool in investment structuring because they roll up largely free of tax inside the wrapper and let you control the timing of when tax eventually falls. This calculator focuses on that timing question: what is left of your tax-deferred allowance today, expressed both as a whole-policy figure and, if you hold a segmented bond, per segment.

How the calculator works

You enter five things: the original amount invested (the premium), the year you invested, the current year, any withdrawals already taken to date, and — optionally — the number of segments your bond is split into. From those inputs it applies the same mechanics HMRC uses for the 5% rule:

• Policy years elapsed = current year − year of investment.
• Annual 5% allowance = original premium × 5%.
• Cumulative allowance = annual allowance × policy years elapsed.
• Remaining allowance = cumulative allowance − withdrawals already taken (never less than nil).

The headline result is the remaining cumulative allowance — the amount you could withdraw this year without triggering a chargeable event. Below it, a breakdown table restates each line so you can see exactly how the figure is built, and if you enter more than one segment it adds a per-segment column (each segment simply carries an equal share of the premium and the allowance). If your withdrawals to date already exceed the cumulative allowance, the tool flags that the allowance is exhausted and that any further withdrawal would create a gain.

The 5% cumulative allowance in practice

The allowance is deliberately generous but often misunderstood on two points. First, it is cumulative: a year in which you take nothing is not lost — the 5% rolls forward, so unused allowances stack up and can be drawn in a later year. Take nothing for eight years and you have built an entitlement to withdraw up to 40% of the original premium in year nine. Second, withdrawals within the allowance are tax-deferred, not tax-free. They postpone the tax rather than removing it: the amounts you take are brought back into account when the bond is finally surrendered, when the whole-life gain is calculated. The allowance is also capped at 100% of the premium — reached after 20 policy years of 5% — after which it is used up. Our guide to offshore investment bonds walks through how these rules interact with top-slicing relief and the final surrender.

Why segments matter

Most offshore bonds are not a single contract but a cluster of identical segments — commonly 100, 1,000 or more. That structure gives you a second lever alongside the 5% allowance: instead of a partial withdrawal spread across the whole policy, you can surrender whole segments. A full segment surrender is calculated on that segment alone, which can produce a smaller or more manageable gain, and segments can be cashed in across different tax years to spread income and make use of allowances and lower-rate bands. The per-segment column in this calculator shows how the premium and allowance divide down, so you can see the building blocks before deciding between a partial withdrawal and a segment surrender — a choice best made with an adviser.

Reading your result — a worked example

Suppose you invested £250,000 in 2015 and it is now 2026, so 11 policy years have elapsed and you have taken nothing so far. The annual 5% allowance is £12,500, giving a cumulative allowance of £137,500 (£12,500 × 11). With no withdrawals to date, the full £137,500 is available this year without triggering a chargeable event — the figure the tool shows as your remaining allowance. If you had already withdrawn £100,000 over the years, the remaining allowance would fall to £37,500. Split the same bond into 100 segments and each segment carries £2,500 of premium and £125 of annual allowance, so the £137,500 headline equals £1,375 of remaining allowance per segment. Note what the number does not tell you: it is the amount you can take tax-deferred now, not a statement of tax due — that only arises if you exceed it or surrender.

Assumptions, limitations and what to do next

The estimate is intentionally simple. It counts whole calendar years rather than exact policy anniversaries, it does not cap the cumulative figure at 100% of the premium once you pass 20 years, and it stops at your available allowance — it does not calculate any tax on a gain, model top-slicing relief or the personal savings allowance, or reflect that a chargeable event gain is taxed as income rather than capital gains. That income-tax treatment is a key contrast with directly held assets: where you would use our Capital Gains Tax calculator for shares or property, a bond gain lands on your income instead. Because an offshore bond rarely sits in isolation, it is worth checking how it fits your inheritance-tax position and your wider tax planning. Use the result here as a starting point, verify it against your policy documents, and take advice before making any withdrawal or surrender. You can find related calculators across our financial tools.