Almost SFr18 million ($15 million) has been made at what has been billed as the world's most important stamp auction in the eastern Swiss town of Wil.
The Rapp auction house had only expected SFr15 million in sales over the four-day event, which offered live bidding over the internet.
Rapp said in a statement late on Thursday that the value of rare stamps had increased despite the global financial crisis.
"Stamps are benefiting from the move towards tangible assets," the auction house said. "The potential for further increases in value is considerable. Many billions of Swiss francs are already being spent on stamps every year throughout the world and this trend is on the increase."
Rapp said thousands of philatelists from more than 30 nations took part in the bidding.
A highlight was the auction of "Rayon I", which went for SFr348,000 to become the most expensive stamp in Switzerland.
The Rayon I was one of the first countrywide stamps to be put into circulation after cantons adopted the federal constitution in 1848. It was then worth five centimes.