The New York-based company reported adjusted quarterly earnings of 58 cents a share, up from 37 cents a year ago, and beat analysts' expectations of 57 cents a share.
Total net income for the fourth quarter was $9.7 million, compared with a net loss of $3.6 million a year ago.
In July, ABM Industries, which provides cleaning and other maintenance services for commercial buildings, hospitals and airports said it was acquiring GCA Services Group for about $1.25 billion in cash and stock.
"We continued to navigate one of the most challenging labor markets in recent history through the implementation of mitigation strategies and we drove GCA-related synergies that exceeded our original in-year expectations," Scott Salmirs, president and CEO, said in a statement. "Additionally, we were able to reduce our leverage beyond our projections due to higher free cash flow generation as a result of our focus on operating efficiencies."
Revenue for the quarter totaled $1.64 billion, up 10.1% from $1.49 billion a year ago, and surpassed expectations by $1.2 million.
For the year, the company reported profit of $97.8 million, or $1.47 a share. Revenue was reported as $6.44 billion.
Looking ahead to 2019, ABM Industries said it expects to earn between $1.65 and $1.80 a share.