The Bern side also booked a spot in next season's Champions League second qualifying round.
Young Boys win fourth straight Swiss league title
Young Boys sealed a fourth consecutive Swiss Super League title with seven matches remaining in the season after a 3-0 home win over Lugano on Sunday.
Cameroon forward Jean-Pierre Nsame scored a hat-trick at the Wankdorf Stadium.
Victory over the visitors earned Young Boys their 15th league crown.
The club urged fans not to congregate in the capital but to party at home instead, due to Covid-19 restrictions on public gatherings.
Instead, they will honour the team's success "together with the fans in an appropriate way after the pandemic".
Young Boys cannot replicate last season's double, having been knocked out of the Swiss Cup in the last 16.
After losing in this season's Champions League third qualifying round, Young Boys made the last 16 of the Europa League but were knocked out 5-0 on aggregate by Ajax.
Aside from the runaway leaders, this season's Swiss top flight has been close, with only nine points separating Vaduz in the ninth-place relegation play-off spot and the top three.
Overall, second-tier Grasshopper Club Zurich have won the most Swiss titles with 27, followed by Basel on 20, Servette on 17 and then Young Boys.
Basel won eight straight championships before Young Boys' current run.
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