Belgium has one national framework for classic vehicles, the O plate, and then three regions that handle tax and inspection in their own way. Knowing which rule is federal and which is regional saves you from reading the wrong page.
The O plate
An oldtimer is a vehicle that has been in use for more than 30 years and is registered under a plate whose letters start with an O. For motorcycles and other category L vehicles the threshold is lower: they can be registered as oldtimers from 25 years of age.
To get the plate the bike goes through an oldtimer inspection at an approved station. You then fill in the registration request with the oldtimer mention, have your insurer submit it with the required documents, and the DIV, the vehicle registration service, issues the plate. If your insurer cannot do it online, the file goes to the DIV by post or at an appointment.
What you give up
An oldtimer may not be used commercially, professionally, to commute to work or school, for paid transport of people, or as a work tool. Commercial use means anything aimed at business or personal financial gain. The O plate is a trade: a lighter regime in return for leisure use.
Inspection
Flanders publishes periodic oldtimer inspection intervals by age: yearly from 25 to 29 years, every two years from 30 to 49 years and every five years from 50 years. That page is written for cars, vans and trailers and says nothing about motorcycles. For motorcycles Flanders has a separate scheme: the inspection applies to bikes over 125 cc after an accident, and since 1 January 2023 also before a second-hand sale, at a price of €57. That sale inspection is meant to be abolished. FEBIAC, the Belgian automotive federation, wrote in July 2026 that the abolition, first planned for July 2026 and then moved to September, has been postponed to the beginning of 2027. Check the Flemish page for the current state before you sell. Wallonia and Brussels have their own rules.
Road tax
Road tax and the one-time registration tax are regional. Flanders has a flat-rate annual tax for oldtimers that applies under conditions, and the amounts are indexed. Look up the figure on the Flemish tax service, not on a forum post from two years ago.
Low emission zones
In the low emission zones of Ghent and Antwerp, an oldtimer older than 30 years with an O plate (or a 1-O plate) can be exempt. You have to register for the exemption; registration is free, you should do it by the day after you first enter the zone, and the exemption is valid without an end date as long as the Flemish rules do not change. The exemption does not apply in Brussels. A foreign-registered vehicle that is at least 30 years old can request a renewable five-year exemption instead.
Buying a bike in Belgium
Ask whether it already carries an O plate and whether the registration documents match the frame number. A bike without an O plate is not automatically an oldtimer on paper, even if it is 40 years old. If you buy from another country, read importing a motorcycle within the EU, and compare the rules in what counts as a classic motorcycle.
