UK Citizen contracted in Spain for global sailing duties

[steviebabes]

Hi all,

Can anyone recommend a recent handbook or guidance note to assist my niece to determine where to declare her income:

Non-resident UK citizen contracts in Spain with a non-EU company to provide work at sea on a non-EU vessel as it pootles around Europe and the wider world.



I, on the other hand, rarely venture beyond my teeny village . . .