Jan 25 (Reuters) - Railroad operator Union Pacific beat estimates for fourth-quarter profit on Thursday on price hikes and volume gains.

Net income attributable to the company for the quarter was $2.71 per diluted share, up from $2.67 per share a year earlier and above analysts' estimates of $2.57 per share.

The company saw a year-on-year gain in freight volumes after a tough few quarters of muted freight demand and higher operating costs.

In response to these headwinds, the Omaha, Nebraska-based company has continued to price its services above inflation, mirroring a trend seen across sectors such as retail and industrials.

However, pricing and volume strength were partially offset by reduced fuel surcharge revenue and a higher proportion of low-margin business.

Operating revenue for the quarter was flat year-on-year at $6.16 billion but came in above analysts' average estimate of $6.05 billion.

(Reporting by Ananta Agarwal in Bengaluru; Editing by Tasim Zahid)