← history
Read stories →
December 6, 1978

1978 Spanish constitutional referendum

Spanish voters ratify the 1978 Constitution

Politics
1978 Spanish constitutional referendum View full image ↗
Illustration generated by Ideogram 4 (fp8) (20 steps, 1216x832) on an NVIDIA RTX 5090 · 2026-08-27
How was this image made?

The creative brief sent to the image model. These are instructions, not a record of what actually happened.

Original prompt & settings (JSON) ↗

The document Spain celebrates every 6 December did not legally take effect until the 29th.

One question on the ballot

On 6 December 1978, Spanish voters answered a single question: do you approve the draft Constitution? The Cortes elected in June 1977 had approved the text on 31 October.

Of 26,632,180 registered electors, 17,873,301 voted — a turnout of 67.11 percent.

The count

15,706,078 voted for the draft and 1,400,505 against. Another 632,902 returned blank ballots, nearly half as many as voted no.

Percentages quoted for the result differ by denominator: the Interior Ministry's 88.54 percent uses all ballots cast, while the commonly cited figure of roughly 92 percent excludes blank and invalid ballots. Turnout was markedly lower in the Basque Country.

Three more weeks to force

The referendum was required by the 1977 Political Reform Law, which obliged the king to submit a constitutional-reform project to a national vote before sanctioning it.

The Electoral Board certified the result on 21 December. King Juan Carlos I sanctioned the Constitution on 27 December, and publication brought it into force on 29 December.

Sources

Researched 23 Aug 2026 6 sources 2 audit passes

How this was checked