Spain’s Ministry of Health has just announced that the country is dropping all Covid related entry requirements for visitors coming from EU and Schengen countries.
So it means that if you’re coming to Spain from one of the EU members states or a Schengen state, you are no longer required to show a vaccination certificate, a negative test or a recovery certificate.

Checks are maintained for travellers from non-EU and non-Schengen associated countries, including at least a temperature check and a documentary check.

You can check out the official BOE, avalaible only in Spanish

This change in rules applies only to visitors from Schengen states and EU member states, so it does NOT apply to visitors coming from the UK or other third countries.
UK visitors are still required to have either a vaccination certificate, a recovery certificate, or a negative test. The passenger locator form is no longer required.