Hi,
Depending on the nature of the services being provided by your company (Company Z) and the length of the contract in Trinidad, it may have a ‘permanent establishment’ (PE) there in accordance with Article 5 of the UK/Trinidad and Tobago Double Taxation Convention (DTC).
If that is the case the profits attributable to the PE would be taxable in Trinidad.
The UK/Trinidad and Tobago DTC can be found at:
UK/TRINIDAD AND TOBAGO DOUBLE TAXATION CONVENTION SIGNED 31 DECEMBER 1982
If a PE does exist then please see:
IINTM281010 - Foreign Permanent Establishments of UK Companies: introduction: overview for further information on how this affects the UK tax position.
However, it is also possible that the salary you receive from Company Z may be taxable in Trinidad if you are present in Trinidad for more than 183 days in the fiscal year concerned and Company Z does not have a PE in Trinidad.
This is covered in Article 15 of the UK/Trinidad and Tobago DTC.
Thank you.