| Competition: | Swiss Promotion League |
| Season: | 2021–22 |
| Winners: | Bellinzona |
| Promoted: | Bellinzona |
| Relegated: | Black Stars Sion U-21 |
| Prevseason: | 2020–21 |
| Nextseason: | 2022–23 |
The 2021–22 Swiss Promotion League is the 10th season (8th under its current name) of the 3rd tier of the Swiss football league system under its current format.
The Championship had 16 teams, of which four were U-21 teams, the eldest youth teams of the Super or Challenge League clubs. The number of U-21 teams permitted in this division was limited to four (this rule would be would be removed for the following season).[1] The U-21 teams are not eligible to promotion or for a slot in the Swiss Cup. The top placed team, of those eligible, would be promoted and the two teams lowest in the table would be relegated. The season was to be played in two stages. In the first stage each team played a double round robin, one at home and one away against each of the other 15 teams. The table was then divided into three groups the teams taking points and goal difference with them. The top six teams played a single round robin, against the other five, for the promotion slot. The following six teams played once against each other for three Swiss Cup slots. The bottom four teams played twice against the others to decide relegation.
The classification also acts as qualifier for the Swiss Cup. The seven highest ranked (eligible) teams qualify directly to the first round of the 2022–23 Swiss Cup. U-21 teams are not eligible for the Swiss Cup.
In the previous season Yverdon-Sport became division champions and had been promoted. Münsingen had ended the season in last position and Köniz in second last position and they were both relegated. Therefore, the 2021–22 season saw three new clubs join the division, Chiasso, after suffering relegation from the 2020–21 Swiss Challenge League, and Young Boys U-21 and Biel-Bienne, who had both been promoted from the 1. Liga.
First stage