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Chargeable event gain calculator
Calculate a bond gain, annual slice and 5% allowance.
Free, no sign-up. AI never does the maths.
Not calculated: a time-apportioned reduction (TAR) from any year of non-UK residence (including a split year), or from an assignment, joint ownership or trust that could give one. If a reduction may apply, tick the box for it under “Does anything unusual apply?” and the withdrawal and segment planners show no tax figures; the raw gain is still shown.
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Chargeable Event Gain
Calculator illustration from paraplanai.co.uk/calculators/chargeable-event-gain · Calculator last reviewed 15 Sept 2026. ParaplanAI keeps no record of this illustration.
For planning and illustration purposes only. Verify all inputs against source documents. This tool does not constitute financial or tax advice.
Print this quick illustration now. Signed-in users can add a client or file reference before saving it as a PDF. Create the compliance annex, with its working and HMRC references, in the signed-in workflow.
Work out a bond's chargeable event gain, annual slice and 5% allowance. These gain figures are before any time-apportioned reduction (TAR).
Free to use, with no sign-up. Your figures stay in this browser unless you choose to share them or send them to your workspace. Calculation methods and checks.
— Understanding the result
A chargeable event gain — the chargeable gain on a UK investment bond — starts with the statutory gain arithmetic. The raw gain shown here is before any time-apportioned reduction (TAR).
On a full surrender it is the surrender value, plus all withdrawals previously taken, minus the total premiums paid and any gains already taxed on earlier excess events.
The gain is then divided by the complete policy years to give the annual equivalent — the raw “slice” before TAR. How to count N, and why a full surrender and an excess event count it differently, is in complete years for top-slicing; the number is usually on the chargeable event certificate.
TAR can apply to qualifying onshore and offshore policies, and UK residence alone does not settle whether it is due. The raw gain remains available. The withdrawal and segment planners assume no TAR is due (no year of non-UK residence, and no assignment, joint ownership or trust that could give one) and say so beside their figures; tick that box in the checklist if a reduction may apply and they show no tax figures. The bond workbench does not calculate TAR either.
Next step
Worked out the gain? Calculate top-slicing relief on it for the full five-step working. The withdrawal and segment planners on this page show relief option by option where they can price it, but not the five steps. With your own gain on screen, the link under the result opens that calculator with your figures filled in.
— How it's calculated
The raw gain on full surrender — before TAR
On a full surrender the chargeable event gain is the surrender value, plus all withdrawals previously taken, minus total premiums paid and minus any gains already taxed on earlier excess events. A negative result means there is no gain; a deficiency arises only where gains on earlier excess events on this policy were taxed on the client, and it is never more than those gains (ITTOIA 2005 ss.540-541). The figure produced at this stage is before any TAR. Background: what a chargeable event gain is, deficiency relief and reporting a gain to HMRC.
IPTM3510 (full surrender) · ITTOIA 2005 s.491 · ss.540-541 · IPTM3870
Check for TAR before using tax-driven comparisons
TAR can affect qualifying onshore as well as offshore policies. Whether it is due can depend on relevant residence, beneficial ownership or assignments, rights held as security, and trust or estate history, so UK residence throughout the policy term alone does not settle the question. This tool does not calculate TAR: raw gain arithmetic stays available, while the comparison and optimisation outputs assume no TAR is due, say so beside the figures, and are withheld if you tick the TAR box.
The 5% tax-deferred allowance
Each policy year you may withdraw 5% of the premiums paid without an immediate chargeable event — unused allowance accumulates, and the pool caps once cumulative allowances reach 100% of premiums (the 20-year point). Withdrawals beyond the cumulative allowance create an excess at the end of that policy year, taxed in the tax year in which that policy year ends. The allowance defers tax; it does not remove it — everything washes through the final surrender computation.
IPTM3540 (part surrenders, the 5% allowance) · ITTOIA 2005 s.507
Segment surrender
Some insurers offer bonds written as a cluster of identical mini-policies (IPTM7230). Surrendering K of the bond’s S whole segments crystallises K/S of the total gain as a final event on those segments. Whether that costs more or less tax than a part surrender of the same cash depends on the bond's gain position, the unused 5% allowance, the client's income and tax year, and the complete years; neither route is better in the abstract (IPTM7330). The comparator prices the routes side by side on the basis that no TAR is due, and says so beside the figures.
IPTM7330 (cluster policies: surrender and part surrender)
Who is taxed on the gain — individual or trustees
The raw gain before TAR uses the same s.491 arithmetic whoever holds the bond: premiums, withdrawals and surrender value. TAR can still depend on beneficial ownership, assignments, security, and trust or estate history. Who pays the tax on the resulting gain also differs. The withdrawal comparator and segment planner above price the tax for an individual chargeable person: top-slicing relief is given only where an individual is liable, and the personal allowance, personal savings allowance and starting rate for savings are individual reliefs. Where UK trustees of a non-charitable trust are the chargeable persons the gain is charged at the trust rate with none of those reliefs, apart from the trust’s low-income rules: up to 2023/24 the first £1,000 of the trust’s income, gain included, is charged at the basic rate (ITA 2007 ss.491–492), and from 2024/25 nothing is due where that income is £500 or less, both amounts being lower where the settlor made other settlements (up to 2023/24 any that existed in the year; from 2024/25 only those with income charged at trust rates in the year, even if within their own tax-free amount, with some kinds of trust not counted) (s.24B) — run that case on the onshore bond tax calculator or the offshore bond tax calculator, which take the chargeable person as an input. While the person who created a non-charitable trust (other than a bare trust) is alive and UK resident, the gain is taxed on that settlor as their own income, whether or not they can benefit (s.465(3)), and the individual treatment applies to the settlor.
ITTOIA 2005 s.535(1) (relief where an individual is liable) · s.465(3) · s.467 · IPTM3230 / IPTM3250
Scottish taxpayers
The gain, the slice and the 5% allowance do not use income tax rates, so they are not affected. A gain is savings income, which is taxed at the same rates across the UK, so the top-slicing relief used in the withdrawal comparator and shown in the segment planner is the same for a Scottish taxpayer. Choose Yes in the calculator to withhold the planners' tax due, net cash, effective rates, tax-free ceilings and tax-based rankings. These rows do not provide the evidence needed to confirm Scottish net tax; use a separate Scottish tax calculation for those figures.
ITA 2007 s.11A(1A) (Scottish rates on non-savings income only) · ITA 2007 s.11D(6) (savings on UK limits)
— How to calculate a chargeable event gain on an investment bond
Step 1
Take the surrender value
Start from the surrender value of the bond, or its value at the chargeable event.
Step 2
Add previous withdrawals
Add any withdrawals previously taken across the life of the policy.
Step 3
Deduct premiums and earlier gains
Subtract total premiums paid and any gains already taxed on earlier excess events.
Step 4
Read the gain
The result is the raw chargeable event gain before TAR. A negative result means there is no gain; a deficiency arises only where gains on earlier excess events on this policy were taxed on the client, and it is never more than those gains (ITTOIA 2005 ss.540-541).
Step 5
Find the slice
Divide the raw gain by N — on a full surrender, death or maturity the number of complete periods of 12 months from the date the policy started to the event, which IPTM7560 distinguishes from the insurance-year count — to get the annual equivalent before TAR.
Step 6
Check for TAR before using tax-driven outputs
The raw gain remains available. The comparison and optimisation figures assume no TAR is due; check relevant residence, beneficial ownership or assignments, security, and trust or estate history, and tick the TAR box if a reduction may apply, when they show no figures.
— Worked example
- Raw gain before TAR (surrender + withdrawals − premiums − previous gains)
- £50,000
- Raw annual equivalent / slice before TAR (gain ÷ 6)
- £8,333.33
- Cumulative 5% tax-deferred allowance to the end of the current insurance year (5% × 7 insurance years)
- £35,000
- Allowance remaining (nothing withdrawn)
- £35,000
Computed live by the same engine the tool above runs. The raw gain and slice are before TAR. The withdrawal-comparison and segment-optimisation figures assume no TAR is due, and show none if you tick the TAR box; this tool does not calculate or apply TAR.
— Frequently asked questions
How is a chargeable event gain calculated on a full surrender?
Take the surrender value, add any withdrawals previously taken across the life of the policy, then subtract the total premiums paid and any gains already taxed on earlier excess events. The result shown by this tool is the raw chargeable event gain before TAR. A negative result means there is no gain; a deficiency arises only where gains on earlier excess events on this policy were taxed on the client, and it is never more than those gains (ITTOIA 2005 ss.540-541).
What is the 5% allowance on an investment bond?
Each policy year you may withdraw 5% of the premiums paid without an immediate chargeable event. Unused allowance accumulates, and the pool caps once cumulative allowances reach 100% of premiums (the 20-year point). Withdrawals beyond the cumulative allowance create an excess at the end of that policy year, taxed in the tax year in which that policy year ends. The allowance defers tax; it does not remove it — everything washes through the final surrender computation.
What is the difference between part surrender and segment surrender?
A part surrender is taxed on the 5% allowance / excess-event basis. A segment surrender crystallises whole mini-policies: surrendering K of S segments crystallises K/S of the total raw gain as a final event on those segments. Whether that costs more or less tax than a part surrender of the same cash depends on the bond's gain position, the unused 5% allowance, the client's income and tax year, and the complete years; neither route is better in the abstract (IPTM7330). The withdrawal comparator prices all three routes side by side on the basis that no TAR is due, and says so beside the figures.
Is the chargeable event gain the same as the slice?
No. The raw slice — the annual equivalent before TAR — is the raw gain divided by N. On a full surrender, death or maturity, N is the number of complete periods of 12 months from the date the policy started to the event. IPTM7560 is explicit that these are periods of 12 months and not insurance years, so an anniversary-based count can differ. On a part surrender or part assignment N is counted to the end of the insurance year in which the event falls, and after an earlier such event from the end of that event’s insurance year. The calculator asks for the complete years the policy has run so far (the anniversaries it has reached). Its withdrawal planner counts a part surrender’s N to the end of the insurance year in progress (that figure + 1), or from the end of an earlier excess event’s insurance year if you enter it. On the day before a policy anniversary a full surrender, death or maturity counts one more complete year than that figure, because IPTM7560 treats the day the policy ends as a full day. This chargeable event calculator produces both: the gain drives the tax computation and the slice drives the relief computation, on the basis that no TAR is due.
Can an investment bond show a taxable gain even if it lost money?
Yes — the 5% allowance trap. Withdrawals above the cumulative 5% allowance create an excess at the end of the policy year in which they are taken, taxed in the tax year in which that policy year ends, even if the bond is worth less than the premiums paid. At final surrender the earlier excess gains are deducted, so no gain is taxed twice, but if the bond ends at a loss the tax already paid is not refunded. Deficiency relief (ITTOIA 2005 s.539; IPTM3880) reduces tax in the year the policy ends, only if the client claims it, only on income taxed at a higher rate (the higher, savings higher, default higher, Welsh higher, Scottish higher or Scottish advanced rate) or the dividend upper rate, only by the difference between that rate and the basic (or dividend ordinary) rate, on no more income than the deficiency: the shortfall at final surrender, capped at the earlier excess gains taxed on the client (ss.540-541; IPTM3870). With no income at those rates that year the client gets nothing back, and additional-rate income is not relieved. The interim charge is real.
Is the gain different if the bond is held in trust?
The raw gain before TAR uses the same surrender-value, withdrawal, premium and earlier-gain arithmetic whoever holds the bond (ITTOIA 2005 s.491). TAR can still depend on beneficial ownership, assignments, security, and trust or estate history, and the tax on the resulting gain can differ. The tax figures in the comparator and segment planner assume an individual chargeable person and that no TAR is due, and are withheld if you tick the TAR box; run a trustee case on the onshore or offshore bond tax calculator.
Does it work for onshore and offshore bonds?
The raw gain before TAR is computed using the same arithmetic for both. TAR can apply to qualifying onshore and offshore policies, while the onshore bond's 20% tax credit applies later in the tax computation. The raw gain remains available whatever you tick; the comparison and optimisation figures assume no TAR is due and are withheld if you tick the TAR box.
Does this calculator apply time-apportioned reduction?
No. It shows the raw gain before TAR. UK residence alone does not settle whether TAR is due: check relevant residence, beneficial ownership or assignments, security, and trust or estate history. The comparison and optimisation outputs assume no TAR is due, say so beside the figures, and are withheld if you tick the TAR box.
— Related
- Investment bonds: the complete guide
- Top-slicing relief calculator — the five-step relief on this gain
- Offshore bond tax calculator — the tax on an offshore gain where no TAR is due, after top-slicing relief where an individual is chargeable
- Investment bond 5% withdrawal allowance: the trap on a bond that lost money
- Part surrender vs segment surrender: same cash, different tax
- What is a chargeable event gain?
- Complete years (N): full surrender vs excess event
- How to read a chargeable event certificate
- Deficiency relief: when a bond ends at a loss
- Reporting a chargeable event gain to HMRC
- Where a chargeable event gain goes on the SA101
- Chargeable events on death
- Full bond TSR workbench — multiple gains, final-year rule, certificate upload and pre-fill (free account)
- See calculation methods and regression evidence
