Over the past two days, more than a thousand people have been airlifted out of the resort which lies at the foot of the Matterhorn after heavy snowfall cut off road and rail links.
Zermatt's tourism office said trains to the nearby village of Täsch resumed at 5.15pm despite efforts to get the service up and running in the morning.
"After almost two days that Zermatt was cut off from the rest of the world, the destination is now reachable by train," it said in a statement.
Excavators had been hard at work around a tunnel between Zermatt and Täsch, which lies about six kilometers away and serves as a gateway to the Matterhorn region.
Onward rail connections out of Täsch remain blocked, but replacement buses are running.
An official with Air Zermatt told AFP that more than 600 people had been airlifted out by helicopter on Tuesday – at a cost of 200 Swiss francs per passenger – with several hundred more flown out on Wednesday.
With the trains still blocked, large queues had built up at the resort's helipad, officials said.
Zermatt, where cars are not allowed to circulate, can accommodate about 13,000 visitors at a time. The resort had been at near capacity during the travel disruptions, although not everyone was trying to leave.
Those stranded there were unable to ski due to avalanche warnings.
Extreme weather has caused havoc in several Swiss areas, including in the canton of Bern where the Lauberhorn World Cup downhill training run had to be cancelled due to snow and high winds.
Other areas in the southern canton of Valais have suffered power outages as well as mud and rockslides and flooding, forcing a number of road closures.