Monarch Scheduled saw carryings rise by almost 50% last month to break through the 300,000 mark for the first time.
The carrier claimed the rise of almost 100,000 year-on-year came as passengers deserted British Airways due to the fallout from the dispute at its catering firm.
Monarch Scheduled flew 303,547 passengers in August, compared with 203,745 in August 2004. The load factor was 87%.
The carrier claims to be the largest international carrier from Manchester as BA drops regional routes, carrying more than 30,000 passengers on a single route (Manchester-Malaga) for the first time in a month.
Monarch Scheduled is to increase services to the Spanish city in November with new routes launching from Blackpool, Newquay and Aberdeen.
Report by Phil Davies
