Federal Act
on the Amendment of the Swiss Civil Code
(Part Five: The Code of Obligations)

¹ The ten­ant may chal­lenge the rent as un­fair and re­quest its re­duc­tion as of the next ter­min­a­tion date where he has good cause to sup­pose that, be­cause of sig­ni­fic­ant changes to the cal­cu­la­tion basis and most not­ably a re­duc­tion in costs, the re­turn de­rived by the land­lord from the leased prop­erty is now ex­cess­ive with­in the mean­ing of Art­icles 269 and 269a.

² The ten­ant must present his re­quest for a rent re­duc­tion in writ­ing to the land­lord, who has 30 days in which to re­spond. Where the land­lord does not ac­cede to the re­quest in full or in part or does not re­spond in good time, the ten­ant may ap­ply to the con­cili­ation au­thor­ity with­in 30 days.

³ Para­graph 2 does not ap­ply if the ten­ant is sim­ul­tan­eously chal­len­ging a rent in­crease and re­quest­ing a rent re­duc­tion.