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HMRC internal manual

Claimant Compliance Manual

Opening and Working Enquiries: NTC enquiry windows - closing dates if customer within SA

If the customer, or either of the customers, is required to make SA returns, the NTC enquiry window will close on the same date as the SA return becomes final. S19(7) says that a return becomes final -

(a) if it is enquired into under section 9A of the Taxes Management Act 1970 (c.9), when the enquiries are completed (within the meaning of section 28A of that Act), or

(b) otherwise, at the end of the period specified in subsection (2) of that section in relation to the return.

If an enquiry has been opened into the SA return, it becomes final for NTC purposes when the notice of completion of the SA enquiry is given.

If no enquiry has been opened into the SA return, it normally becomes final for NTC purposes a year after the filing date.

However, the position can be different so you should follow the guidance (including examples) as follows: -

In addition to the above, there is some general guidance about NTC enquiries for SA taxpayers at CCM12680 and 12690.