(Reuters) - Xcel Energy ( XEL ) reported an increase in fourth-quarter profit on Thursday, as the utility firm benefited from higher electricity rates and lower operating expenses.

The company reported a rise in earnings in Minnesota and Colorado regions, on higher recovery of electric and natural gas infrastructure investments.

Regulated utilities use rate case proceedings to seek a rate increase based on their investments or expenses to provide services.

The Minneapolis, Minnesota-based company also benefited from lower quarterly operating expenses, which were down 3.3% at $2.77 billion from a year earlier.

The utility firm's net income was up 13.4% at $464 million for the quarter ended Dec. 31.

Xcel Energy ( XEL ) serves a total of 3.7 million electricity customers and 2.1 million natural gas customers across eight states of Colorado, Michigan, Minnesota, New Mexico, North Dakota, South Dakota, Texas and Wisconsin.