Operating profit in the three months to the end of September rose from €818m to €1.2bn. Total revenue increased by 15% to €6.8bn.
Willie Walsh, IAG chief executive, said: "We’re reporting strong quarter results with a positive contribution from all of our airlines.
"We’re delighted to announce IAG’s first dividend payment of 10 euro cents per share.”
Along with BA, IAG owns Iberia, Vueling and Aer Lingus, which it bought earlier this year.