Shares of CBIZ Inc (NYSE: CBZ) plummeted 5.03% in pre-market trading on Wednesday after the company reported a significant net loss in the fourth quarter of 2024, weighed down by costs related to its acquisition of Marcum LLP.

The professional services firm posted a net loss of $90.7 million, or $1.53 per diluted share, for the quarter ended December 31, 2024. This compares to a net loss of $12.7 million, or $0.26 per share, in the same period a year earlier. Adjusted for one-time items, CBIZ reported an adjusted net loss of $0.20 per share, beating analysts' expectations of a $0.24 loss.

Revenue for the quarter surged 40.5% year-over-year to $460.3 million, driven by the Marcum acquisition, which closed on November 1, 2024. On a same-unit basis, revenue increased by 6.4%.

For the full year 2024, CBIZ reported revenue of $1.81 billion, up 14% from 2023, and adjusted earnings per share of $2.67, a 10.8% increase. The company's GAAP earnings per share for the full year was $0.78.

Looking ahead to 2025, CBIZ expects total revenue in the range of $2.9 billion to $2.95 billion and adjusted earnings per share between $3.60 and $3.65. The company's GAAP earnings per share guidance is $1.97 to $2.02.

The fourth-quarter loss and elevated costs were primarily driven by the Marcum acquisition, which added significant scale to CBIZ's financial services practice. The company recorded $57.1 million in operating losses during the two-month post-acquisition period, as well as $55.5 million in acquisition-related costs, including transaction expenses and incremental interest expenses.

CBIZ's management remains optimistic about the long-term benefits of the Marcum deal, stating that the combined entity has solidified its position as the largest provider of professional services to middle-market businesses. However, the near-term financial impact appears to have spooked investors, leading to the sharp sell-off in the stock.