Malmöhus County
Until 1968, the City of Stockholm had its own "county code" A, which is still used interchangeably with AB in some contexts, and County of Stockholm had county code B. L was for Kristianstad County and M was for Malmöhus County but since they were merged to form Skåne County, M is usually used. O used to stand for Gothenburg and Bohus County but has been used for Västra Götaland County since it was merged with Skaraborg County (R) and Älvsborg County (P).