Ryanair has expanded its reserved seating policy from 40 to 80 routes and chief executive Michael O'Leary expects to roll it out across the fleet by next summer.
The Irish carrier began experimenting with offering reserved seating for a premium initially on a couple of routes but has seen strong uptake on some of its longer routes.
"It is running as high as 20% on some of the longer routes," O'Leary said during a first-half results conference in London today.
He noted this has been the big growth in ancillary revenues in the first half, alongside longer average sector lengths giving it "more time to sell more things" to passengers.
He said the carrier had rolled the concept out gradually to ensure it did not impact punctuality and its 25min turnaround time, but that there has been no such impact and it plans to expand it beyond the 80 routes on which it is now available.
"I think by next summer it will be across the whole network," he said.