Most brokers in Switzerland will charge you a fee for actually holding your account, usually a certain percentage of all the holdings worth’s, mostly with a lower limit.

As with all cost these costs must be taken into consideration when calculating your return on investment.

Side note:
The only Swiss broker known to us that doesn't charge a maintenance fee is Yellowtrade, the online broker of Postfinance. But in return they only trade stocks, but no mutual funds nor even ETF's *.
So if you plan to implement an index based investment strategy it won't happen with them.

*(as of the 1st of July 2003: Some ETF's on SWX might be traded. Experience shows that the tradability of these instruments can be withdrawn any time, as occurred with certain ETF's traded on the NYSE)