Hi njc23,
The annual exempt allowance is available to the owner of the property.
If the property is jointly owned, then both owners can claim the annual exempt allowance.
In 23/24 tax year this is £6000.
In 24/25 it is reduces to £3000.
Your income from renting the property meet the criteria for completing a self assessment tax return, even if you are not resident in the UK.
Check if you need to send a Self Assessment tax return.
Thank you.