The Rolling Meadows, Illinois-based company said it had net income of 62 cents per share.
The results met Wall Street expectations. The average estimate of nine analysts surveyed by Zacks Investment Research was also for earnings of 62 cents per share.
The insurance and risk-management company posted revenue of $1.66 billion in the period. Its adjusted revenue was $1.63 billion.
Arthur J. Gallagher shares have increased 12 percent since the beginning of the year. In the final minutes of trading on Thursday, shares hit $71.17, a climb of 21 percent in the last 12 months.