Application for UK S1 - when can we apply ?

Hi, apologies if this info is somewhere on the forum but I can't find anything that relates to it.

Does anyone know the process for applying for an S1 in the UK, specifically, when to apply ?.

I'm not sure if we can apply before we leave the UK to live in Spain or whether we have to wait until we physically arrive in Spain ?.

Thanks. Paul.

Ideally you need an address in Spain and you should apply for it about 3 weeks before you move over. It will then be sent to your address in Spain.

However, if you can't do this then you can apply for it when you move to Spain but it will delay the process.

Thank you Marcliff, straight forward.

I was told by Dwp to apply for 4 weeks before taken up residence in Spain the relevant forms then arrived at Spanish address within 2 weeks from applying

I used my Spanish lawyers address had them sent there before I moved.

Thanks all for the feedback.