5After that section insert—
(1)This section applies if the individual has unused annual allowance available for the tax year (“the current tax year”).
(2)The annual allowance for the current tax year in the case of the individual is to be treated as increased by the amount of the unused annual allowance available for the current tax year.
(3)The individual has unused annual allowance available for the current tax year if—
(a)the amount of the annual allowance (before any increase under this section) for the immediately preceding tax year exceeded the total pension input amount in the case of the individual for that tax year, or
(b)the amount of the annual allowance (before any such increase) for either or both of the two tax years immediately preceding that immediately preceding tax year exceeded the total pension input amount in the case of the individual for the tax year concerned and the excess (or, where there is an excess for both of those tax years, the excess for both tax years) has not been used up,
or both.
(4)Subsection (3)—
(a)does not apply in relation to a tax year preceding the current tax year unless the individual was a member of a registered pension scheme at some time during that tax year, but
(b)subject to that, applies in relation to such a tax year even if the total pension input amount in the case of the individual for that tax year was nil (in which case the excess within paragraph (a) or (b) of that subsection is the whole amount of the annual allowance before any increase under this section).
(5)The amount of the unused annual allowance available for the current tax year is the aggregate of—
(a)any excess within subsection (3)(a), and
(b)so much of any excess within subsection (3)(b) as has not been used up.
(6)An amount of an excess within subsection (3)(b) for a tax year has been “used up” if—
(a)for a tax year falling between that tax year and the current tax year (an “intervening tax year”), the total pension input amount in the case of the individual exceeded the annual allowance (apart from any increase under this section), and
(b)the amount of the excess had effect by virtue of this section to reduce (or eliminate) the annual allowance charge for the intervening tax year in the case of the individual.
(7)In calculating for the purposes of subsection (6) the amount of which of the excesses for different tax years had effect to reduce or eliminate the annual allowance charge for an intervening tax year, an amount of the excess for an earlier tax year is to be taken to have done so before that for a later tax year.”