IATA initially had scheduled the switchover to e-tickets, eliminating paper tickets, to be completed by December 31.
The decision to extend the deadline was taken at the three-day IATA annual conference in Vancouver that opened Sunday and should "support the carriers that need more support," said IATA director general Giovanni Bisignani.
IATA spokesman Anthony Concil said that to date 80 percent of the association's members have implemented the e-ticket.
"We estimate this figure should be around 94 percent by the end of December," he said.
The spokesman declined to identify the laggard companies.
"What takes more time are the interline agreements between our members and other companies" who are not IATA members, he said.
"Some travel agencies also prefer to keep on using paper ticket for a while.
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He explained the conversion to all e-ticketing was a process that requires close consultations with small partner companies which are loath to give up paper tickets.
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