Section 690 | Internationally mobile employees ^F1

(1)This section applies in relation to an employee if the employee is or has been internationally mobile at any time in tax year 2025-26 or a subsequent tax year.

(2)An employee is “internationally mobile” at a time in a tax year if at that time the employee works or is likely to work both inside and outside the UK during the tax year (“the mobile tax year”) and at that time—

(a)the employee is or is likely to be non-UK resident for the mobile tax year, or

(b)the mobile tax year is or is likely to be a split year as respects the employee.

(3)If the employer makes an uncertain payment to the employee in any tax year, the entire uncertain payment is to be treated for the purposes of PAYE regulations as a payment of PAYE income of the employee.^F2

(4)For the purposes of this section and sections 690A and 690B, an “uncertain payment” means a payment or part of a payment of, or on account of, the income of the employee in respect of which—^F3F4

(a)the employer is unable to ascertain the extent to which the income relating to that payment or part is PAYE income, and^F5

(b)the reason for the employer being unable to ascertain that extent is connected to the employee being or having been internationally mobile in the mobile tax year.

(5)Subsection (3) is without prejudice to—

(a)any assessment in respect of the income of the employee in question, and

(b)any right to repayment of income tax and any relevant debts overpaid and any obligation to pay income tax underpaid and any relevant debts that remain wholly or partly unpaid.

(6)For the purposes of this section and sections 690A to 690E—

(a)any reference to a payment made by the employer includes a reference to a payment made by a person acting on behalf of the employer and at the expense of the employer or a person connected with the employer, and

(b)in a case where section 689 or 689A applies, any reference to a payment made by the employer is to be read as a reference to a payment treated, for the purposes of PAYE regulations, as made by the relevant person.