Subsections (2) and (3) apply for the purpose of calculating the amount of the charge to tax under section 4 on a person's death if the person dies on or after 6 April 2017.
If the person's residence nil-rate amount is greater than nil, the portion of VT that does not exceed the person's residence nil-rate amount is charged at the rate of 0%.
References in section 7(1) to the value transferred by the chargeable transfer under section 4 on the person's death are to be read as references to the remainder (if any) of VT.
The person's residence nil-rate amount is calculated in accordance with sections 8E to 8G (and see also section 8M).
For the purposes of those sections and this section—
but this is subject to subsections (6) and (7),
but is nil if that amount is greater than the person's default allowance.
Subsection (7) applies if—
Unless Parliament otherwise determines, the amount of each of—
is its amount for the prior tax year increased by the same percentage as the percentage increase in the index and, if the result is not a multiple of £1,000, rounded up to the nearest amount which is such a multiple.
The Treasury must before 6 April 2021 and each subsequent 6 April make an order specifying the amounts that in accordance with subsections (6) and (7) are the residential enhancement and taper threshold for the tax year beginning on that date; and any such order is to be made by statutory instrument.
In this section—
"consumer prices index" means the all items consumer prices index published by the Statistics Board,
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