Inheritance tax calculator

By SwiftWillUpdated 24 September 2026England and Wales

Quick answer

Enter the estate's value, what goes to a spouse, civil partner or charity, and the value of any home passing to children or grandchildren. The calculator applies the £325,000 nil-rate band, the residence nil-rate band of up to £175,000 with its taper above £2 million, allowances transferred from a late spouse or civil partner, and the 36% rate when enough goes to charity. It gives an estimate, not a tax return or advice.

Estimate the inheritance tax on an estate

For deaths from 6 April 2026 to 5 April 2031. Figures stay in your browser.

Estate value after debts (£)Home, savings, investments, possessions and your share of joint assetsLeft to a spouse or civil partner (£)Left to charity (£)Value of the home, or share, left to children or grandchildren (£)Direct descendants only: not nephews, nieces or siblingsGifts in the 7 years before death, after exemptions (£)Widowed, or a surviving civil partner, and the late partner’s allowances will be claimed

Estimate

Exempt (spouse and charity): £0
Chargeable estate: £600,000
Residence nil-rate band used: £175,000
Nil-rate band used: £325,000
Taxable amount: £100,000

Estimated inheritance tax

£40,000

£100,000 at 40%.

Unused allowance that could pass to a surviving spouse or civil partner: 0% of the nil-rate band and 0% of the residence band.

An estimate, not a tax return or advice. SwiftWill does not do tax planning. How inheritance tax works.

What does the calculator include?

It works out the tax charged on an estate at death, using the allowances and rates for deaths from 6 April 2026 to 5 April 2031. The nil-rate band, residence nil-rate band and £2 million taper threshold are frozen for that whole period by Finance Act 2026 (Finance Act 2021, section 86, as amended).

What the estimate covers and what it leaves out
Included	Not included
£325,000 nil-rate band, reduced by gifts in the seven years before death	Tax on the gifts themselves, taper relief and who pays it
Residence nil-rate band, capped at the home passing to direct descendants	Downsizing additions and the choice between several homes
The £2 million taper, applied to own and transferred residence band	Agricultural and business property relief
Unused percentages transferred from a late spouse or civil partner	Trusts, gifts with reservation and foreign tax credits
Spouse, civil partner and charity exemptions	The £325,000 cap on gifts to a spouse who is not a long-term UK resident
The 36% rate when at least 10% of the baseline amount goes to charity	Grossing up, quick succession relief, interest and instalments

How does the calculator work out the tax?

It follows the order set by the Inheritance Tax Act 1984 and HMRC guidance:

Take off exempt gifts. What goes to a spouse, civil partner or charity is deducted from the estate value to give the chargeable estate.
Work out the residence nil-rate band. Start with £175,000, plus any transferred percentage. Reduce it by half of the amount by which the whole estate, before exemptions, exceeds £2 million. Then limit it to the value of the home passing to direct descendants (section 8D).
Apply the nil-rate band. £325,000, plus any transferred percentage, less gifts made in the seven years before death.
Check the charity rate. The baseline amount is the chargeable estate less the available nil-rate band, with the charity gift added back. The residence band is not deducted. If the charity gift is at least 10% of that, the rate is 36% (HMRC manual IHTM45009).
Charge the rate on whatever is left above the allowances.

It also shows how much of each band would be left unused. That matters for married couples and civil partners, because the unused percentage can be claimed on the survivor’s death. See transferring nil-rate bands between spouses.

What results should you expect for common estates?

These examples use the calculator’s method. The first five reproduce examples published by GOV.UK and HMRC.

Worked examples, deaths from 6 April 2026 to 5 April 2031 unless stated
Estate	Allowances used	Result
£500,000, no home to descendants (GOV.UK overview)	£325,000 nil-rate band	£70,000 tax
£300,000 home and £190,000 other assets to children (GOV.UK, 2020 to 2021)	£175,000 residence band and £315,000 nil-rate band; £10,000 of nil-rate band left to transfer	No tax
£100,000 flat and £400,000 to a son, £500,000 to a husband (GOV.UK, 2020 to 2021)	£100,000 residence band (the flat’s value) and £325,000 nil-rate band; £75,000 taxable	£30,000 tax
£2.2 million estate, half of a £500,000 home to a grandson (HMRC, 2020 to 2021)	Residence band tapered from £175,000 to £75,000, less than the £250,000 half-share	£75,000 residence band
£750,000 with £50,000 to charity (HMRC)	£325,000 nil-rate band; baseline amount £425,000, so 36% applies	£135,000 tax, against £170,000 with no charity gift
Widowed, £1.1 million including a £450,000 home to children, both bands fully unused	£650,000 nil-rate band and £350,000 residence band	£40,000 tax
Widowed, £2.2 million including a £600,000 home to children, both bands fully unused	£650,000 nil-rate band and £250,000 residence band after a £100,000 taper	£520,000 tax

Sources for the published examples: GOV.UK overview, GOV.UK residence nil-rate band guidance, IHTM46027 and IHTM45010.

Why might HMRC’s figure be different?

Valuations. HMRC can check property and share values, and the estate is taxed on the agreed figures.
Debts and funeral costs. Only allowable debts come off. Enter the estate value after them.
Joint property. Where land or property was owned as joint tenants with people other than a spouse or civil partner, GOV.UK’s estimating rules divide the value between the owners and take 10% off the share (GOV.UK: estimate the estate’s value).
Reliefs. Business, agricultural and other reliefs can reduce the value. From 6 April 2026, 100% relief is limited to the first £2.5 million.
Pensions. For deaths on or after 6 April 2027, most unused pension funds count. See pensions and inheritance tax.
Interest. Tax paid after the end of the sixth month after death carries interest.

What should you do with the result?

If you are planning ahead and the estimate shows tax, the next step is advice, not a template. Inheritance tax planning, such as trusts, lifetime gifting strategies, and business or agricultural property, needs individual advice from a solicitor or tax adviser. SwiftWill’s automated will does not do tax planning: it records who inherits, and its suitability check points people who want to plan around inheritance tax to a solicitor. Read do I need a solicitor for a will?

If you are an executor, use the estimate to decide what to expect, then follow HMRC’s process: value the estate, check whether full details are needed, and pay by the end of the sixth month after the death. Our inheritance tax guide and the executor checklist explain the steps, and the probate fees estimator covers the court fee.

To understand the allowances behind the numbers, read the residence nil-rate band explained, gifts and the seven-year rule and leaving money to charity in a will.

Sources

Sources checked 24 September 2026.

Which related guide should you read next?

Can I leave my house to my children? — Leaving a home to children in England and Wales: joint ownership, the mortgage, children under 18, stepchildren, a surviving spouse and the residence band.
Will cost over time calculator — Compare published will prices and optional annual update costs with explicit assumptions. Unknown fees stay unmodelled; services differ.
Intestacy flowchart — Answer up to four questions to see who inherits under the England and Wales intestacy rules, with the full order of relatives and the £322,000 spouse legacy.
Probate checker: do I need probate? — Answer up to three questions about property, joint assets and what banks have told you to see whether an estate in England or Wales needs probate.

Frequently asked questions

What allowances does the inheritance tax calculator use?

The £325,000 nil-rate band and the residence nil-rate band of up to £175,000, both frozen until 5 April 2031, with the residence band reduced by £1 for every £2 the estate is worth over £2 million. If you tick the widowed option, it adds the percentage of a late spouse's or civil partner's bands that you enter.

Does a surviving spouse automatically get double the allowances?

No. Only the unused percentage of the late spouse's or civil partner's bands can be added, and the survivor's executors must claim it. The full £1 million also needs a home worth at least £350,000 passing to direct descendants and an estate of no more than £2 million.

How does leaving money to charity change the result?

The charity gift is exempt, so it comes off the taxable estate. If it is at least 10% of the baseline amount, which is the chargeable estate less the available nil-rate band with the charity gift added back, the rest is taxed at 36% instead of 40%. The calculator shows the amount needed.

Why does the calculator ask for the value of the home?

The residence nil-rate band can never be more than the value of the home, or share of it, that passes to direct descendants. A £120,000 flat left to a son supports £120,000 of residence band, not £175,000.

Does the calculator include pensions?

Only if you add them to the estate value. For deaths before 6 April 2027 most unused pension pots are outside the estate. For deaths on or after that date, most unused pension funds and death benefits count, so include them when estimating for the future.

Is this the same as HMRC's inheritance tax checker?

No. HMRC's online checker helps executors decide whether tax is likely but does not calculate the amount. Neither tool replaces the IHT400 account, where HMRC works out the tax from the executors' valuations.

Record who inherits in a straightforward will

SwiftWill prepares simple England and Wales wills. It does not do inheritance tax planning.

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