(1)The buyer in a land transaction must make a return to WRA if—
(a)section 19 or 20 (contingent, uncertain or unascertained consideration) applies in relation to the transaction, or to any transaction in relation to which the transaction is a linked transaction,
(b)an event mentioned in subsection (2) occurs, and
(c)the effect of the event is that—
(i)the transaction becomes notifiable,
(ii)additional tax is payable in respect of the transaction, or
(iii)tax is payable in respect of the transaction where none was payable.
(2)The events are—
(a)in the case of contingent consideration, the contingency occurs or it becomes clear that it will not occur, or
(b)in the case of uncertain or unascertained consideration, an amount relevant to the calculation of the consideration, or any instalment of consideration, becomes ascertained.
(3)A return made under this section must—
(a)be made before the end of the period of 30 days beginning with the day after the day on which the event mentioned in subsection (2) occurred, and
(b)include a self-assessment.
(4)Despite section 157(3) of TCMA (late payment interest), the late payment interest start date in relation to an amount—
(a)stated in a return made under this section as the tax payable,
(b)payable as a result of an amendment or correction to such a return,
(c)payable as a result of an assessment made in addition to such a return, or
(d)payable as a result of a determination or an assessment made in place of such a return,
is the day after the end of the period of 30 days beginning with the day after the effective date of the transaction (and Chapter 1 of Part 6 of that Act is to be read accordingly).
(5)The Welsh Ministers may by regulations amend subsection (4) so as to substitute for the period for the time being specified there, a different period.
(6)This section does not apply in so far as the chargeable consideration consists of—
(a)rent (see Schedule 6);
(b)an annuity to which section 21 applies.