JetBlue Airways Corp. said its second-quarter earnings rose 18% and the discount carrier continued to benefit from low fuel costs.

Shares, down 18% this year, rose 7.5% to $18.57 in recent trading as per-share earnings beat expectations.

Robin Hayes, JetBlue's chief executive, in an interview with The Wall Street Journal, also said the New York discount carrier is considering adding its first routes to Europe.

JetBlue also said that it placed orders for 30 single-aisle A321 planes from Airbus Group SE, some of which will be used for JetBlue's premium Mint service that flies on transcontinental routes and to the Caribbean.

Over all, JetBlue reported a profit of $180 million, or 53 cents a share, up from $152 million, or 44 cents a share, a year earlier. Revenue increased 1.9% to $1.64 billion amid 10% growth in passenger traffic that helped offset an 8.8% decline in average fares.

Analysts polled by Thomson Reuters expected per-share profit of 49 cents and revenue of $1.65 billion.

Passenger unit revenue—a measure of sales per seat flown a mile—declined 11%.

JetBlue reported that capacity expanded by 11%. However, the percentage of seats filled, or load factor, declined by 0.6 percentage point to 85%.

Operating expenses per seat mile, excluding fuel and profit-sharing, fell 1%. Jet Blue said its fuel prices declined by a third.

Write to Tess Stynes at tess.stynes@wsj.com

(END) Dow Jones Newswires

July 26, 2016 11:55 ET (15:55 GMT)