Geneva international airport and the EuroAirport in Basel were closed on Wednesday morning due to heavy snowfall.
In Basel the closure coincided with a strike by French airport staff.
In Geneva, up to 30 flights were cancelled before the first plane took off at 11.30 a.m. The number of Basel flights cancelled or unable to land reached 24. Basel managed to re-open its runways at 9.40am.
Passengers intending to travel to Britain may be worst affected during the day because of heavy snowfall at British airports.
The airports have advised passengers with flights scheduled for Wednesday to check with their airline for possible delays before travelling to Geneva or Basel.
It has been a rocky start to the year for Geneva airport. Striking ground staff just ended their ten-day protest action on Tuesday over salary and work conditions.
swissinfo.ch and agencies