Social Security Contributions

I was resident and working as Autonomos in Spain for over 15 years and I'm now working elsewhere abroad. As can be done in the UK, can I make voluntary S.S. contributions in Spain in order to maintain any future pension entitlements?

You used the term was a resident...so I take it you are no longer a resident in Spain... in that case why would you want to make NI contributions to the Spanish government of  approximately €250 per month when you don't live in Spain...if you are in residence  in the UK for instance you would pay NI contributions to the UK government ..the same goes for any other country you now resident in....maybe when you get to pension age for Spain you will able to claim a small pension for the 15 years contributions you paid in ...I don't think you will get the answer to this on EOS you will need to consult a Tax account in Spain.

PS .if you can afford it Pay your €250 into a private pension scheme ...this will give you much more than a couple of hundred euro's per month that... the Spanish pension state pension will pay out think about it.

Not longer a resident, but I am hoping to in the future. From what I understand to be entitled to a reduced spanish state pension I have to have contributed  for 15 years but two of those years have to be within 10 or 15 years ?? before retirement. It's over 15 years ago that I made the S.S. contributions so I have to make at least another two years. With Brexit I may not be able to make those two other contributions and therefore was wondering if its possible to make volunartary contributions when I am not resident there, as can be done in the UK for expats. I am hoping to be elegible for a full UK state pension AND a part Spanish pension, independently, and not to count the contributions together to make up one full pension. I understand that this is possible. A part pension may be small, but I would need a substantial  amount in the bank earning interest to generate this income, and therfore it may be worth pursuing. Thanks for you previous response.

https://www.expatica.com/es/finance/retirement/pensions-846584/