linguistic:paraphrasing, information:highlighting
Elsewhere

In Hungary, similar to Ireland, motorway numbers can be derived from the original national highway numbers (1–7), with an M prefix attached, e.g. M7 is on the route of the old Highway 7 from Budapest towards Lake Balaton and Croatia. New motorways not following the original Budapest-centred radial highway system get numbers M8, M9, etc., or M0 in the case of the ring road around Budapest.

In the Netherlands, motorway numbers can be derived from the original national highway numbers, but with an A (Autosnelweg) prefix attached, like A9.

In Germany federal motorways have the prefix A (Autobahn). If the following number is odd, the motorway generally follows a north–south direction, while even-numbered motorways generally follow an east–west direction. Other controlled-access roads (dual carriageways) in Germany can be federal highways (Bundesstraßen), state highways (Landesstraßen), district highways (Kreisstraßen) and city highways (Stadtstraßen), each with their own numbering system.

In Italy, motorways follow a single numbering, even if managed by different concessionaire companies: they are all marked with the letter "A" (for autostrada; "RA" in the case of motorway junctions, with the exception of the Bereguardo - Pavia junction numbered on the signs as Autostrada A53, and "T" for the international Alpine tunnels) followed by a number. Therefore a motorway with the same numbering can be managed by different concessionaire companies (for example the Autostrada A23 is managed for a stretch by Società Autostrade Alto Adriatico and for the remaining stretch by Autostrade per l'Italia).

In New Zealand, as well as in Brazil, Russia, Finland, and the Scandinavian countries, motorway numbers are derived from the state highway route that they form a part of, but unlike Hungary and Ireland, they are not distinguished from non-motorway sections of the same state highway route. In the cases where a new motorway acts as a bypass of a state highway route, the original state highway is either stripped of that status or renumbered. A low road number means a road suitable for long-distance driving.

In Belgium, motorways but also some dual carriageways have numbers preceded by an A. However, those that also have an E-number are generally referenced with that one. City rings and bypasses have numbers preceded by an R; these also can be either motorways or dual carriageways.

In Croatia, motorway numbering is independent of state route numbering. Motorways are prefixed by an A (for autocesta), as in many other European countries. Some motorways are the result of an upgrade of an older two-lane road, and carry concurrencies with state routes. In some other cases, such as with the A2, following the upgrade, the state route was rerouted onto the frontage road.