I am a UK citizen and taxpayer on retirement extension in Thailand. I have a UK property which i rent out using a managing agent, just got my last statement and their was a 76 GBP deduction for something called Overseas Tax Q1 which when i looked it up on the internet was to do with the Internal Revenue Service USA. when my letting agents open in the UK i will contact them to find out what is happening in the meantime who and how do i contact and complain to in the IRS

I suspect it has nothing to do with the US IRS.

Wait until your agent replies and explains the deduction - Its either a mistake or HMRC related.

https://www.gov.uk/guidance/paying-tax-on-rent-to-landlords-abroad#the-non-resident-landlord-scheme

https://www.gov.uk/guidance/paying-tax-on-rent-to-landlords-abroad#the-non-resident-landlord-scheme

Thanks for the information but i already fill in a self assessment tax return in which the rental income is included and pay tax on the income to HMRC

Looks like you need to ensure you receive a Certificate of Tax Liability from your Letting Agent which confirms tax payable by them on your behalf. This can then be included in your self assessment as an offset against your tax liability.

https://www.gov.uk/government/publications/non-resident-certificate-of-tax-liability-to-be-provided-to-non-resident-landlords-by-uk-letting-agents-or-tenants-nrl6