Construction on the M-18 highway finished in 1965. However, asphalt was not applied along the highway until years later.[1]
In January 2016, the Ministry of Transport and Maritime Affairs published bylaw on categorisation of state roads.[2] With new categorisation, M-18 highway was split in two new highways, M-3 highway and M-4 highway.
^Doderović, Miroslav; Ivanović, Zdravko (Fall 2012). Drumski saobraćaj u Crnoj Gori [Vehicular transport in Montenegro] (PDF) (in Montenegrin). Matica crnogorska. p. 484. Retrieved 24 May 2015. "Put Šćеpаn Pоljе – Nikšić – Pоdgоricа – Tuzi – Bоžај, prеdstаvljа diо magistralnog puta M-18, kојi pоčinjе na mаđаrskој grаnici, а zаvršаvа sе na Božaju (аlbаnskа grаnicа). Krоz Crnu Gоru prоlаzi u dužini оd 162 km, а svојim gеоgrаfskim pоlоžајеm zаuzimа јеdnо оd cеntrаlnih mјеstа u оkviru putnе mrеžе Crnе Gоrе. Put је bеz аsfаltnоg kоlоvоzа zаvršеn 1965. gоdinе, а kаsniје sе pаrciјаlnо pristupаlо аsfаltirаnju pојеdinih diоnicа.
^"Pravilnik o kategorizaciji državnih puteva" [Regulation on categorisation of state roads]. www.sluzbenilist.me (in Montenegrin). Official Gazette of Montenegro. 5 January 2016. Retrieved 14 February 2019.