UK Inheritance Tax Calculator for Married Couples

Combine two nil-rate bands and two residence bands — up to £1,000,000 tax-free

Married couples and civil partners can combine two nil-rate bands and two residence bands — up to £1,000,000 of IHT-free allowance. On a £1,200,000 estate that cuts the tax from £280,000 (one person's bands) to £80,000. It runs free in your browser on Gera Tools, with nothing uploaded.

Last updated Source: Gera Tools

How much can a married couple leave tax-free?

Up to £1,000,000 when a home passes to children — two £325,000 nil-rate bands plus two £175,000 residence bands. Without a home to descendants the figure is £650,000.

When the first spouse or civil partner dies, anything left to the survivor is exempt from Inheritance Tax, and the survivor inherits the unused percentage of the first partner’s allowances. With both nil-rate bands and both residence bands, a couple can shelter up to £1,000,000 when a home passes to children.

The £1,000,000 couple allowance

AllowancePer personCouple
Nil-rate band£325,000£650,000
Residence nil-rate band£175,000£350,000
Combined (home to children)£500,000£1,000,000

Worked example — £1,200,000 estate, home to children

ScenarioTax-free bandsIHT due
One person’s bands only£500,000£280,000
Both bands transferred£1,000,000£80,000
Saving from the transfer£200,000
StepAmount
Net estate£1,200,000
Less nil-rate band−£650,000
Less residence nil-rate band−£350,000
Taxable estate£200,000
Rate40.0%
Inheritance Tax due£80,000

How the transfer works

The transfer is by percentage, not a fixed sum. If the first spouse used none of their nil-rate band (because everything passed to the survivor), 100% transfers — doubling the band. Executors claim it on the second death using forms IHT402 (nil-rate band) and IHT436 (residence band).

The current UK Inheritance Tax rules

Allowance / rateAmountNotes
Nil-rate band (NRB)£325,0000% on this slice of every estate
Residence nil-rate band (RNRB)£175,000Only when a home passes to direct descendants
Taper threshold£2,000,000RNRB falls £1 for every £2 of estate above this
Standard rate40.0%On the estate above the available bands
Reduced charity rate36.0%If ≥10% of the net estate goes to charity

Sources & as-of