Yes, up to 3.5 tonnes an e-vignette is required. Light buses usually have a higher seating capacity than 7 seats and therefore use the category D2 (Check categories here), while coaches exceed 3.5 tonnes.
Vehicles (and vehicle + trailer combinations) that have a total permissible weight of over 3.5 tonnes use the distance based toll system (HU-GO).
You can order your Hungarian e-vignette now comfortably here.
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