The Exeter-based carrier's load factor jumped to 75.8% in the quarter to June 30, up from 66.5% a year earlier as it benefits from a turnaround drive that recently saw it post annual profits for the first time in four years.
Chief executive Saad Hammad said first quarter trading figures signalled further progress, helped by last summer's launch of 11 new routes and a major brand refresh in April when it unveiled aircraft in a new purple livery.
The airline, which serves around 35 UK airports having reduced its number of bases from 13 to seven in the last year, said passenger revenues per seat rose 9.5% in the quarter to £52.79.
This was achieved after a recent route overhaul reduced capacity by 17.2% to 2.5 million seats for the quarter to June 30. It has also cut the average fare paid per passenger in an effort to drive demand.
Mr Hammad said: "We have achieved a significant amount in the quarter, with substantially more to do in the months ahead."
Shares were 2% higher today and have risen 17% so far this year.
The group has its regional bases in Belfast, Birmingham, Edinburgh, Exeter, Glasgow, Manchester and Southampton. It also has a white label business with Finland's Finnair, where it flies planes under the airline's livery.