IAG said it expected passenger unit revenue to improve for the rest of the year on a constant currency basis.
The company also saw passenger revenues surge for the half-year, with revenues rising 7.2% to 10.6 billion euros (£9.7 billion) over the first six months of 2019.
Willie Walsh, IAG chief executive, said: "Despite fuel cost headwinds, we delivered a good performance". Passenger unit revenue for the quarter grew 3.1% or 1.1% at constant currency, boosted by the later timing of Easter this year.
Earlier this week, BA failed in a bid to challenge the legality of a strike ballot organised by BALPA, the pilots' union, which had recorded overwhelming support for the threatened action.
In results published on Friday, IAG said BA would "vigorously defend itself" against a record £183m fine imposed by the Information Commissioner's Office (ICO) following a major data breach past year.
The interim results come two days after British Airways lost an appeal aimed at stopping a planned strike by pilots.
"Given all the uncertainties over global growth and Brexit, this looks to be a very strong statement by the company and implies that forward bookings are trending well", Goodbody analyst Mark Simpson said in a note.
Total revenues increased by 10 percent to nearly 6.8 billion euros.
While Walsh said he was anxious about the economic impact of Britain's plan to leave the European Union on October 31, he had not yet seen any impact on bookings.