# Finance Act 2026, Paragraph 22: Supplementary assessments

Extent: E+W+S+N.I.

(1) Sub-paragraph (2) applies where—
(a) an assessment has been notified to a person under paragraph 20(2), and
(b) it appears to an officer of Revenue and Customs that the amount which ought to have been assessed as due exceeds the amount that has already been assessed.
(2) The officer of Revenue and Customs—
(a) may make a supplementary assessment of the amount of CBAM due from the person to the best of their judgement, and
(b) where such an assessment is made, must notify the person of that amount.

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Source: https://www.legislation.gov.uk/ukpga/2026/11/schedule/17/paragraph/22 (the official version)
Page: https://openlegislation.uk/finance-act-2026/schedule-17/paragraph-22
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.