A £2,000,000 estate is above a single person's £500,000 allowance, so tax is due: £600,000 at 40% on the amount above it. A married couple or civil partners combining both allowances up to £1,000,000 still owe tax at this size — £400,000 — but pay less because more of the estate sits within the combined allowance.
The £175,000 residence nil-rate band only applies when a qualifying home goes to direct descendants. Without it, a single person's allowance drops to £325,000.
Spouses and civil partners pass unused allowance to each other, lifting the combined headroom to £1,000,000.
Gifts made within seven years of death can use up the nil-rate band first, increasing the tax on what remains.
Leaving 10% or more of the net estate to charity cuts the 40% rate to 36% on the rest.
Most unused pension funds join the taxable estate from 6 April 2027, which can push a £2,000,000 estate into a higher tax figure.