An individual who is resident in the UK and another country (a dual resident) may pay tax on their income twice. Where a double taxation agreement (DTA) is in force between the countries, the taxpayer may be able to claim double tax relief in the UK. The claim is made in boxes 20, 21 or 22 of the SA109 supplementary pages to the tax return, as appropriate.  

In its latest Agent Update, HMRC says that errors are commonly made in completing the boxes and that this can give rise to additional tax liabilities, interest and penalties for the taxpayer. To help prevent this, HMRC recommends that taxpayers and agents refer to the following guidance when completing their return:

• the notes accompanying SA109; 
• HMRC’s guidance on how DTAs work; and
• helpsheets HS302 (box 21) and HS304 (box 20 and 22). 

HMRC is also reminding taxpayers that where a claim is made in boxes 20-22, the taxpayer will need to attach the following to their return:

• their certificate of residence from the other tax authority; and
• the HS302 or HS304 claim form, as appropriate.