Vehicles registered in Slovakia are generally assigned to one of the districts (okres) and since 1997, the licence plate coding (Slovak: EČV, evidenčné číslo vozidla) generally consists of seven characters and takes the form XX-NNNLL, where XX is a two letter code corresponding to the district, NNN is three digit number and LL are two letters (assigned alphabetically).
There are three design varieties that are in valid use.
Where limited space warrants it, two-line plates can be used on a vehicle. A block of combinations is set aside from the regular plate range as required.
There are 79 districts in Slovakia. In 69 cases, the district is named after and the code derived from its principal city which is included in the district. Two cities, Bratislava (the capital) and Košice (KE), consist of 5 and 4 districts respectively. This fact is not reflected on the plates, only one code is used. Additionally, Košice-okolie (KS) comprises an area around Košice (the city itself excluded) while having its seat in the city proper. Each district is assigned at least one code. Eight cities that are also seats of the region (kraj) are assigned more. Since 18 August 2010, Bratislava has been registering plates with its second code, BL. Bratislava is the only okres to do so and will remain in this position for years as Košice, the runner-up, has only reached the Hx series as of March 2011.
The older system (Slovak: ŠPZ, štátna poznávacia značka) XX NN-NN or XXY NN-NN - was issued until 30 March 1997. All such registrations expired on 1 January 2005, vehicles that had not registered under the new system are not allowed on public roads.