| Season: | 1972–73 |
| Competition: | Nationalliga A |
| Winners: | Basel |
| Relegated: | Fribourg Grenchen |
| League Topscorer: | Ottmar Hitzfeld (Basel) and Ove Grahn (Lausanne-Sport) both 18 goals |
| Prevseason: | 1971–72 |
| Nextseason: | 1973–74 |
| Season: | 1972–73 |
| Competition: | Nationalliga B |
| Winners: | Xamax |
| Promoted: | Xamax CS Chênois |
| Relegated: | SC Brühl SC Buochs |
| League Topscorer: | Jean-Robert Rub (Xamax) and Guy Mathez (Xamax) both 18 goals |
| Prevseason: | 1971–72 |
| Nextseason: | 1973–74 |
The following is the summary of the Swiss National League in the 1972–73 football season, both Nationalliga A and Nationalliga B. This was the 76th season of top-tier and the 75th season of second-tier football in Switzerland.
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. Two points were awarded for a win and one point was awarded for a draw. 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 champions would qualify for the 1973–74 European Cup. The second and third placed teams were qualified for the 1973–74 UEFA Cup. The last two placed teams were to be relegated.
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 top two teams would be promoted and the last two teams relegated.[1]
The first round of the NLA was played on 14 August 1972. After playing 13 rounds, there was a winter break, held between 5 December and the 14th round on 5 March 1973. The season had 26 rounds and was completed on 10 June 1973.
| Team | Town | Stadium | Capacity | |
|---|---|---|---|---|
| FC Aarau | Aarau | Stadion Brügglifeld | ||
| AC Bellinzona | Bellinzona | Stadio Comunale Bellinzona | ||
| FC Biel-Bienne | Biel/Bienne | Stadion Gurzelen | ||
| SC Brühl | St. Gallen | Paul-Grüninger-Stadion | ||
| SC Buochs | Buochs | Stadion Seefeld | ||
| CS Chênois | Thônex | Stade des Trois-Chêne | ||
| Étoile Carouge FC | Carouge | Stade de la Fontenette | ||
| FC Luzern | Lucerne | Stadion Allmend | ||
| FC Martigny-Sports | Martigny | Stade d'Octodure | ||
| Mendrisiostar | Mendrisio | Centro Sportivo Comunale | ||
| Vevey-Sports | Vevey | Stade de Copet | ||
| FC Wettingen | Wettingen | Stadion Altenburg | ||
| Xamax | Neuchâtel | Stade de la Maladière | ||
| FC Young Fellows Zürich | Zürich | Utogrund | ||
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.