Spain's self-employed have until August 31 to reset their contribution base for September 1

Eight days left in the window. Spain lets the self-employed (autónomos) change their social-security contribution base up to six times a year in two-month windows, and requests filed between July 1 and August 31 take effect on September 1. Miss it and the next reset is November 1, from requests filed in September and October.

Who should care: anyone whose 2026 income forecast has drifted from the base they picked. Earning more than planned, raising the base now shrinks the year-end regularization bill; earning less, lowering it cuts the monthly payment from September. The filing is done online through the Import@ss portal and lands automatically on September’s bill.

If you freelance from Spain (or advise someone who does), run the numbers before touching anything; the base drives both the monthly payment and the eventual settlement against real income.

Our take: Spain’s true-up at year end forgives very little, and these bimonthly windows are the cheap lever most people never pull.