Global Water Resources (GWRS) reported a Q1 loss late Wednesday of $0.01 per diluted share, compared with earnings of $0.02 a year earlier.
One analyst surveyed by FactSet expected a loss of $0.02.
Revenue in the three months ended March 31 rose to $13.3 million from $12.5 million a year earlier.
Two analysts polled by FactSet expected $14.1 million.
The company's shares rose 1.8% in after-hours trading.