Import tax

I don't know what you mean by a 'polar'. 

However, if this is your one-off permanent move, then you are not liable for Import Duty or IVA - as long as all the goods are your own, you've owned them for more than 6 months in the UK and you don't sell them within a year of moving to Spain.

Thanks for that. I meant podar, not polar! My reading of the Northern Ireland protocol is that for the movement of goods, NI is still considered part of the EU for the free flow of goods. 

podar

ENGLISH

prune

verb

I think it is connected to cropping / pruning the value of something (which could be likened to applying a tax?)

I think you meant Padron, which is literally a census of "residents" not non residents who shouldn't have it anyway. Your courier should be following the rules regarding NI and if as you say you still have free movement no taxes are applicable. Talk to your Couriers again, before Brexit whilst in the EU we traveled with a van full of our own belongings and needed no paperwork nor any tax applied so it should be same for you now. I, m not familiar with what parts of Ireland are still in EU but I think they are treating you as UK and not in EU. 

Regards 

Pauline