The classic con: you pay for gas AND a service contract on the gas boiler AND a chimney sweep. Ever seen any soot from gas? I thought not. In another other country this would be laughed out of court...

We've had gas in all of our appartments (Canton Geneva), but had to supply our own appliances if we wanted to use it.

As with electricity, the tenant normally enters into a contract with the suppliers and pays for what they've used over a monthly or quarterly billing period.

The 'charges'; which cover the running costs of the building (heating, water, concierge, maintenance) are estimated and are based on previous years and the tenant will usually pay these monthly, with an annual round-up billed/refunded after all the yearly bills are in.

As Longbyt says, this has been covered several times in other threads.

Our previous apartment in Canton Zurich did have a gas stove, boiler etc. but it is not common in Switzerland because of the high costs and gas supply is simply not available everywhere.

In our case, most costs were shared between neighbours but the gas would only be charged by usage. However the fix rate for the supply was much higher than the actual usage. Gas is fantastic for cooking, but it is quite an expensive luxury.