Taxation (International and Other Provisions) Act 2010 section 134

Correcting assessments where relief is available

Section 134 allows HMRC to make correcting assessments where double taxation relief is available but the original assessment is wrong — either because it does not cover the full amount of income or gain, or because the tax credit has not been properly taken into account.

• Where double taxation relief is available (under a treaty or unilateral relief), HMRC can issue correcting assessments if the original assessment does not reflect the full amount of income or chargeable gain, or does not properly account for the foreign tax credit due.
• The correcting assessments may be made to ensure the full income or gain is assessed and the correct credit for foreign tax is given; if income is paid through a UK-based agent or intermediary, the assessment can be made on the recipient of that income.
• The relevant taxes covered are income tax, corporation tax, and capital gains tax; in all cases the gain must be a "chargeable gain" because the provisions relate to UK tax liabilities.
• HMRC officers also have the power to amend assessments, determinations, or decisions on claims that are necessary as a consequence of the double taxation relief rules as they apply for petroleum revenue tax purposes.