SM-Sarja was the top level of ice hockey in Finland from 1928 to 1975. SM-sarja is a common abbreviation for Suomen mestaruussarja, "Finnish Championship Series".
There was variable number of teams playing for the Finnish championship during the time of SM-sarja. Lowest number of participating teams was during the 1935 SM-sarja season when there was 3 teams. The most common number of participating teams was 12.
Since 1944-45 SM-sarja season there was relegations for lowest ranking teams of each season. In the relegations the lowest ranking teams either faced the winner of the 1. Divisioona(1st Division) or was straightly relegated from SM-sarja.
SM-sarja was played in amateur principles so the clubs were not supposed to pay their players beyond compensation for lost wages. However as Ice Hockey evolved in Finland some teams were started to be handled like businesses. In 1960's, two leading Finnish household machine factories UPO and Rosenlew established their own Ice Hockey teams, Upon Pallo and Rosenlewin Urheilijat-38. These teams were run by the money of the owning companies and the players were bought from the neighbouring teams. This would be the first steps towards professionalism.
By 1970's the concept of Amateur ice hockey was turning out of date as there was commercials on players uniforms and bigger money involved in teams and in 1975 SM-sarja played its last season and was replaced by SM-liiga for 1976 season.
The last team to win the Finnish championship under SM-sarja was Tappara
After 1933 SM-sarja was contested as a league. In 1951 SM-sarja was divided to 2 groups and the Play Offs were introduced.
The SM-sarja moved back to one group play in 1959 though the two group-system returned for 1965-66 SM-sarja season.