May 30 (Reuters) - Costco Wholesale Corp's quarterly comparable-store sales in the United States missed Wall Street estimates on Thursday, as the warehouse club operator struggled to lure shoppers in a competitive grocery space.
Shares of the Issaquah, Washington-based company were down about 1% in extended trading.
Costco faces competition from retail giants Amazon.com Inc and Walmart Inc, who are slashing prices and widening their offerings while also improving their mobile apps and speeding up delivery.
Comparable-store sales, or those recorded at Costco's e-commerce platform and warehouses open for more than a year in the U.S., rose 5.5%, excluding the impact of fuel and currency fluctuations. Analysts were expecting growth of 5.62%, according to IBES data from Refinitiv.
Overall comparable-store sales, excluding the impact of fuel prices and currency changes, rose 5.6%, above analysts' average estimate of a 5.48% rise.
Excluding one-time items, Costco earned $1.89 per share in the third quarter ended May 12. Total revenue rose 7.4% to $34.74 billion.
Analysts, on average, had expected the company to post a profit of $1.82 per share on revenue of $34.71 billion. (Reporting by Nivedita Balu in Bengaluru; Editing by Shailesh Kuber)