List of international vehicle registration codes

The country in which a motor vehicle's vehicle registration plate was issued is indicated by an international licence plate country code, formerly known as an International Registration Letter or International Circulation Mark, displayed in bold block uppercase on a small white oval plate or sticker near the number plate on the rear of a vehicle.

The allocation of codes is maintained by the United Nations Economic Commission for Europe as the Distinguishing Signs Used on Vehicles in International Traffic (sometimes abbreviated to DSIT), authorised by the UN's Geneva Convention on Road Traffic of 1949 and the Vienna Convention on Road Traffic of 1968. Many vehicle codes created since the adoption of ISO 3166 coincide with ISO two- or three-letter codes.

The 2004 South-East Asian Agreement ... for the Facilitation of Cross-Border Transport of Goods and People uses a mixture of ISO and DSIT codes: Myanmar uses MYA, China CHN, and Cambodia KH (ISO codes), Thailand uses T (DSIT code), Laos LAO, and Vietnam VN (coincident ISO and DSIT codes).

In the European Economic Area, vehicles from one member state do not need to display the oval while within another state, provided the number plate is in the common EU standard format introduced in the 1990s, which includes the international vehicle registration code on the plate.

Note: an asterisk (*) indicates that this code is unofficial (does not appear in the UN list of distinguishing codes).

Immediately after Croatia's declaration of independence in 1991,
it was common to see unofficial oval stickers with the letters "CRO".
Despite the initial anticipation that Croatia's international vehicle registration code would be "CRO", Croatia opted for "HR" (Hrvatska) instead.
SHS was for the Kingdom of the Serbs, Croats (H) and Slovenes.

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