Shares in Shake Shack were up more than 8 percent in extended trading.
Analysts had expected the company to report a loss of 3 cents a share on $34 million in revenue, according to a consensus estimate from Thomson Reuters.
Shake Shack announced 2015 guidance that was a little lighter than expected. Total revenue for the year is projected to be between $161 million and $165 million with sales growth in the low to mid single digits. The company also expects to open at least 10 stores throughout the year.
"We are pleased to have continued our strong momentum through the first quarter," CEO Randy Garutti said in a press release. "Our strong track record of opening successful Shacks in both the United States and internationally continues to demonstrate the global appeal of Shake Shack and validates our belief in our significant whitespace opportunity."
Shake Shack reported first-quarter sales increased 59 percent to $36 million year over year, while same-store sales rose 11.7 percent.
The company had a net loss of $12.7 million, or $1.06 per diluted share, which included $13 million in after-tax expenditures related to its initial public offering, compared with profit of $1.1 million a year earlier.
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During the quarter Shake Shack opened three domestic company-operated Shacks, including a first store in Baltimore and two additional locations in the Boston market.
Shake Shack made its public debut in late January, in what S&P Capital IQ calls the best-performing IPO of 2015. Its shares have soared and more than tripled in price. Wall Street, however, is cautious on the restaurant's stock with an average "hold" rating, according to FactSet.