You can contribute without working: all you need is for Social Security to accept it

Spain’s Social Security system has a special agreement that lets people keep paying contributions even if they stop working.

To qualify, applicants usually need at least 1,080 contributed days in the last 12 years and cannot be collecting unemployment, insured under another regime, or receiving a pension.

The request must be filed within one year of the event that triggers eligibility, and the monthly fee is set by Social Security based on the contribution base chosen.

The scheme can help workers preserve contribution records and protect future pension rights, but they must pay the cost themselves.