Registration numbers in Spain
There have been three main formats of Spanish vehicle registration plates. Until the early 1970's plates just included the province and a sequential number. This system was discarded in October 1971 when Barcelona and Madrid both nearly reached 999999.

The next system was in the form of XX NNNN YY where XX was the province code and NNNN was a sequential number, followed by two letters. Some letters were not used. This system became flawed when the Spanish langauages were changed as some provinces changed their names/spelling. Madrid was also reaching ZZ so numbers were running out.

These keep the old system of letter code plus numbers.

• CME - Cos de Mossos D'esquadra (Corp of Mossos d'Esquadra). The autonomous police force of Catalonia

• DGP - Dirección General de la Policía ("Spanish Police")

• CNP - Cuerpo Nacional de Policía (since 2008)("Spanish Police")

• E - Ertzaintza. (autonomous police force of the Basque Country)). The E has a special "wiggly" form.

• EA - Ejército del Aire ("Spanish Air Force")

• ET - Ejército de Tierra ("Spanish Army")

• FN - Fuerzas Navales / Armada ("Spanish Navy")

• GSH - Gendarmería del Sahara ("Spanish colonial police on Sahara"). Not longer existing.

• PGC - Parque de la Guardia Civil ("Spanish civil guard", a militarized police force similar to French "Gendarmerie Française" or Italian "Corpo dei Carabinieri")

• MF - Ministerio de Fomento ("Public Works Ministry") (no correlativity with MOP)

• MMA - Ministerio de Medio Ambiente ("Environment Ministry")

• MOP - Ministerio de Obras Públicas ("Public Works Ministry") (now replaced by MF)

• PME - Parque Móvil del Estado (state owned vehicles)

• PMM - Parque Móvil del Ministerio (state owned vehicles, on a Ministry) (now replaced by PME)