# The Taxes (Interest Rate) (Amendment) Regulations 2026, Regulation 2: Amendment of the Taxes (Interest Rate) Regulations 1989


(1) The Taxes (Interest Rate) Regulations 1989 are amended as follows.
(2) After regulation 3ZE, insert—
“Applicable rate of interest on unpaid multinational top-up tax and domestic top-up tax
3ZF (1) For the purposes of paragraph 33 of Schedule 14 to the Finance (No. 2) Act 2023, with respect to unpaid multinational top-up tax and domestic top-up tax, the rate applicable under section 178 shall, subject to paragraph (2), be 7.75% per annum.
(2) Where on a reference date after 17th April 2026 the reference rate found on that date differs from the established rate, the rate applicable under section 178 for the purposes mentioned in paragraph (1) shall, on and after the next operative date, be the percentage per annum found by applying the formula specified in paragraph (3).
(3) The formula specified in this paragraph is—
R R + 4 , where RR is the reference rate referred to in paragraph (2).
Applicable rate of interest on overpaid multinational top-up tax and domestic top-up tax
3ZG (1) For the purposes of paragraph 33A of Schedule 14 to the Finance Act (No. 2) 2023, with respect to overpaid multinational top-up tax and domestic top-up tax, the rate applicable under section 178 shall, subject to paragraph (2), be 2.75% per annum.
(2) Where on a reference date after 17th April 2026 the reference rate found on that date differs from the established rate, the rate applicable under section 178 for the purposes mentioned in paragraph (1) shall, on and after the next operative date, be the higher of—
(a) 0.5% per annum, and
(b) the percentage per annum found by applying the formula specified in paragraph (3).
(3) The formula specified in this paragraph is—
R R - 1 , where RR is the reference rate referred to in paragraph (2).”.

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Source: https://www.legislation.gov.uk/uksi/2026/347/regulation/2 (the official version)
Page: https://openlegislation.uk/taxes-interest-rate-amendment-regulations-2026/regulation-2
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.