Non-UK residents are only subject to UK tax on their UK income. The way in which non-UK residents pay tax in the UK will depend on their specific circumstances, such as the nature of their UK income, the amount of income they earn, and whether there is a double taxation agreement between the UK and their country of residence.
If a non-UK resident receives income from a UK source, such as rental income from a UK property or UK employment income, they may have to register for and pay UK tax. They will need to register with HM Revenue & Customs (HMRC) by completing a tax return, and pay any tax due by the deadline.
However, if there is a double taxation agreement in place between the UK and the non-UK resident's country of residence, they may not have to pay tax twice. They may be able to claim relief from UK tax, or claim a credit for any UK tax paid against their home country's tax liability.
It is recommended that non-UK residents seek the advice of a professional tax advisor to ensure that they meet their UK tax obligations and do not pay more tax than they need to.