90 day rule & NLV & taxes

Re 90 days yes, once you've had 90 days in a rolling 180 then you must leave and not return for a further 90 days. It's the Schengen area BTW, not just Spain.

If you become Spanish resident then you pay tax in Spain on your worldwide income. You cannot come on an NLV if you are still employed somewhere although you can draw dividends.

Use a Schengen calculator as the 180 days is rolling, not in one lump. You don't have to leave for 90 days if the first day you came was more than 90 days ago within that 180. I always found this one to be good Schengen Calculator but there are others. As pointed out before, there are no 2 x 180 blocks but the dates are rolling.

As Darro says, to get an NLV you have to show a P45 to show you are no longer working or a final tax statement if you are self employed. The non lucrative bit means just that. There are other visas such as digital nomad, self employed, entrepreneur and so on but all have their own system for applying. You couldn't keep running a business in UK with an NLV.  You could take dividends as income but not profits. Yes, they would be taxable in Spain.

There is a dual tax agreement so you don't pay tax on the same income twice. 

On the face of it, and this is not something I've looked at in detail but on the assumption you wish to carry on working for your own business (whether as an employee of that business or as self employed) and that work can be carried out remotely, then it would seem the digital nomad visa would seem to fit the bill.

Digital Nomad Visa in Spain: a Complete Guide (With Tax Benefits) (balcellsgroup.com)

Regarding the Schengen 90/180 point, then it is as Marcliff explains - as it is rolling, then days start dropping off at the back end.

So if for example I was a UK resident and left Spain on the 5th January 2024 having been here since the 10th December 2023 - the 10th December day would start dropping off from the 90/180 calc at the 7th June 2024 (possibly +/- 1 day based on my Excel). It doesn't stay on the record because it forms part of the block that ended on the 5th January 2024. Each day in Schengen is treated independently and is why things like the calculator can be useful if you intend to get close to or around the maximum on a forever rolling basis.

You can:

Come for 3 month (90 days) then go for 3 months (90 days) then come back for 3 month.

Come for 3 weeks then go for 3 weeks.then come back for 3 weeks.

Come for 1 month then leave for a month then come back for a month and so on.

Basically, an equal amount of time in Spain (or Schengen country) upto 90 day max and an equal amount of time out.

Below calculator is quite good.

https://ninety180.com/

This link explains the requirements for a NLV:

https://www.exteriores.gob.es/Consulados/Manchester/en/ServiciosConsulares/Paginas/Consular/Visado-de-residencia-no-lucrativa.aspx

This link gives a good overview of the Double Taxation Agreement between the UK and Spain:

https://expatsmagazine.org/double-taxation-agreements-spain-uk/

HI Jo

https://www.visa-calculator.com/

I use this it seems the best of the lot and it’s free and keeps you aligned very easy to use

As RonTT has highlighted the 90 day/180 day can be split however you wish. 

The optimum period for equal Spain/home country would be 45 days in each country (excluding travel time), so not too bad really. At least until you retire.