A social plan is in place for the 140 employees affected by the shutdown, said the company, which is still actively seeking new owners.
Hello ceased operating its four Airbus A320 aircraft as of 11pm on Sunday following the cancellation of two large contracts with tour operators.
“The reason for the bankruptcy is the financial implosion of two large customers, ever higher fuel costs and the strong Swiss franc, which led to the cancellation of a contract with Tui Germany,” the company said in a statement.
“Also, there is an increasingly fierce competition in the tourism business.”
Hello's CEO Robert Somers, an Irish expat, told The Local "there is a possibility" the airline could resume operations if it can find new owners.
"We were in bankruptcy court in Basel this morning and they gave us until at least the end of November to find a buyer," Somers said.
"Five different parties" were interested in taking over the airline, but whoever takes over will have to recapitalize the company, he said.
Hello said that booking errors made by the former chief financial officer, who left the company in September, contributed to the company’s difficulties.
“All the business figures supplied to the board and the management on a weekly and monthly basis turned out to have been incorrect,” according to the company statement.
Based on the numbers given, the company’s management and board were convinced sufficient funding was available but “this was not the case”.
A new chief financial officer hired by the company uncovered the situation but efforts to recapitalize the company have failed.
Somers said the former CFO tendered his resignation in June to take effect in September.
The company, he said, was looking into whether the bad financial advice was simply a case of incompetence or otherwise.
Hello has informed the tour operators it worked with and said they are already looking for alternative opportunities for their clients.
The airline was established in 2003 by entrepreneur Moritz Suter, beginning operations the following year as a regional scheduled carrier.
Suter is the largest of eight shareholders in Hello, Somers said.
The carrier recently came under fire from Aeropers, the Swiss Air Line Pilots Association, for hiring inexperienced co-pilots who worked for free in return for gaining flying time.