Low-cost carrier Frontier Airlines is adding non-stop service in 42 markets across the country, including new service from Minneapolis-St. Paul to Chicago's O'Hare Airport.

The Twin Cities to Chicago service will begin April 15.

The introductory fare will be $29 each way, rising to $59 after the promotion period ends. Most other new routes will have introductory fares of $39 and up, the airline said.

The breakdown of the introductory one-way ticket is $4.57 for the actual fare and $24.43 for taxes and fees, for a total of $29. The airline's one-way fee for a carry-on bag starts at $35.

Tickets must be purchased by 11 p.m. central time Jan. 17 for nonstop travel through Aug. 15.

"Travelers between big cities have enjoyed low fares while many markets have remained overpriced and underserved," said Frontier Airlines President Barry Biffle. "Frontier's low fares in these new markets will benefit millions of new fliers who are forced to drive because they haven't found affordable air travel options – or they simply stay at home. We see hundreds of additional opportunities like these throughout the country, fueling our growth for years to come."

American Airlines recently announced it will add three daily non-stops between the Twin Cities and Washington D.C. beginning April 5.

The airline will use a combination of American Eagle Embraer E-170s and E-175s, which seat between 69 and 76 passengers.

American Airlines joins Delta and Sun Country as the third airline at MSP to offer nonstop service to Washington National Airport.