The Swiss Football Association (ASF/SFV) had 28 member clubs at this time and these were devided into two divisions of 14 teams each.
The teams played a double round-robin to decide their table positions.
The top tier (NLA) was contested by the top 12 teams from the previous 1971–72 season and the two newly promoted teams FC Chiasso and FC Fribourg.
The second-tier (NLB) was contested by the two teams that had been relegated from the NLA, FC Biel-Bienne and Luzern, the teams that had been in third to twelfth position last season and the two newly promoted teams Young Fellows Zürich and SC Buochs.
The decider match for second place was played on CS Chênois won and were promoted to 1973–74 Nationalliga A. Luzern remain in the division.