INTM343120 | DT applications and claims - Types of income: Pensions and Annuities
From HM Revenue & Customs · International Manual
Merchant Navy pension
When a seafarer retires, the treatment of their pension should follow the established treatment of their wages. If their wages were subject to PAYE (because they worked for a UK employer performing duties in the UK) their pension is also liable to UK tax.
Sometimes a seafarer receives a Merchant Navy pension and is resident in a country that either does not have a Double Taxation Agreement (DTA) with the UK, or where the treaty does not have a pensions article.
Where there is no pension article in a DTA or no double taxation treaty at all, you have to consider
The location of previous employment duties.
The person’s residence status whilst carrying out these duties.
And the provisions of PAYE81750
in order to decide if the pension is exempt from the operation of PAYE.