Every three months the rate of interest used to set Swiss rents is reviewed. If it goes down some renters have the right to request a decrease in rent. On 1 June 2015 it was reduced from 2.00% to 1.75% so many currently have a chance to reduce their rent.
The interest rate used to set the reference rate is the average rate on Swiss mortgages at 31 March 2015. This rate is 1.86%, which rounds to 1.75% under the rounding rules. The average rate at 31 December 2014 was 1.89%, only 0.03% higher, however under the rounding rules, which round to the nearest 0.25%, 1.89% rounded to 2.00%.
This latest reference rate drop to 1.75% is the first since September 2013.
In general if your rental contract links your rent to mortgage interest rates then you can demand a decrease in rent when this reference rate declines. The Swiss Association of Tenants, Romande branch, provides useful information on when and how to go about making a demand. Their website (in French) can be found at www.asloca.ch.
When the reference rate declines those with such rental contracts should act smartly to ensure they get the maximum benefit as many landlords will not spontaneously offer the reduction and you can be fairly sure that landlords will be quick to increase your rent when the reference rate climbs.
The next reference rate will be announced on 1 September 2015.
Current and historical reference interest rates are presented on the Office Fédéral du Logement (OFL) website.