The Spanish registration plate system has experienced many changes, with the most recent coming into force in September 2000.

Until the start of the 1970s, number plates in Spain consisted purely of a province code followed by a series of digits. Some vehicles carrying these marks can still be seen on the country’s roads today. This system became exhausted when the cities of Madrid and Barcelona both ran out of digit combinations.

The system that followed took the form of two letters, followed by four numbers, with a one or two letter suffix combination. As with the old format, the first two letters denote the province code, while the four digit number exists purely to differentiate between cars with the same province code and suffix combination.

Province codes usually follow a particular format by taking the first two letters of the province, following the regulations introduced in 1926. Province code problems began to surface when registered keepers travelled to other areas of the country, due to rivalries between regions. As this system neared its end, Madrid and Barcelona were, once again, running out of combinations.

The key change with the introduction of new system is that it is no longer province specific and is, instead, uniform across the whole country. The new number plates follow the format of four digits followed by three letters. There are, however, some letters that are not used, these being A, E, I, O, Q, U and Ñ. The numbers run from 0000 to 9999 and while the letters give no indication of where the vehicle was registered, they may give some indication as to the age of the vehicle.