Aon PLC’s first-quarter revenue increased as its reinsurance broking and benefits consulting business grew by high-single-digit percentages, but it continued to see pressure in its U.S. retail business.

The brokerage, which Thursday announced that its $13 billion purchase of middle-market brokerage NFP Corp. closed ahead of schedule, expects to acquire more smaller brokers.

Aon reported first-quarter revenue of $4.07 billion, a 5.1% increase over the same period last year, and a similar level of organic growth, which excludes the effect of mergers and acquisitions and foreign exchange fluctuations.

The organic growth rate was lower than several of its rival publicly traded brokers that reported first-quarter results over the past two weeks.

On a regional basis, Aon’s retail brokerage business saw solid growth in Europe, the Middle and Africa, Asia and the Pacific, but results in the United States “were pressured, reflecting lower net new business and the ongoing impacts from external capital markets activity,” the brokerage said in its earnings release.

On a call with analysts Friday, Aon CEO Greg Case said certain areas of its large commercial business, such as directors and officers liability insurance, have seen pressure on rates.

In addition, “we were very underweight in the past toward middle market — until yesterday — and now we see a massive opportunity going forward,” he said, referring to the NFP deal.

In previous quarters, Aon said a drop-off in revenue from transactional risk insurance, due to the general slowdown in mergers and acquisitions, has been a drag on U.S. revenue.

The M&A market remains “fairly depressed,” said Eric Andersen, Aon’s president.

Aon reported revenue of $1.81 billion in commercial risk solutions, its main retail brokerage unit, a 1.7% increase over the same period last year, and up 3% on an organic basis; in reinsurance broking, it reported $1.17 billion in revenue, up 8.4% overall and 7% on an organic basis.

Revenue for health solutions, its health and benefits consulting unit, totaled $733 million, up 9.2% overall and 6% on an organic basis; wealth solutions, its retirement services unit, had revenue of $370 million, up 5.7% overall and 4% on an organic basis.

Aon reported net income of $1.09 billion for the quarter, up 1.3%.

The purchase of NFP, announced in December, was expected to close this year, but Aon had conservatively based its financial metrics for the deal on a 2025 close.

The enterprise value of the deal was $13 billion, $6 billion from Aon shares and $7 billion in cash, Aon said.

Based on 2023 revenue, NFP adds $2.19 billion in total revenue to Aon, comprising $1.04 billion in health solutions, $761 million in commercial risk solutions, and $392 million in wealth solutions, Aon said in its earnings presentation.

The companies’ combined revenue for 2023 totaled $15.57 billion.

NFP has been an active buyer of smaller brokerages over the past several years.

“We’re incredibly excited about NFP’s impressive M&A engine, noting their strong history of M&A. We look forward to building on their established track record and executing against their strong pipeline,” said Christa Davies, Aon chief financial officer.

Aon announced earlier this month that Ms. Davies will retire in 2025.