Frontier Airlines is saving some green for people named "Green" to celebrate "Green Week."

The airline has been offering special promotions all week, but Thursday's maybe the most lucrative. The airline announced that it is giving away free round-trip flights to people with the last name "Green" or "Greene."

Of course, there are some stipulations with Frontier's offer. The departure flight must depart on Aug. 13, and the return flight must arrive home by 11:59 p.m. on Aug. 20.

Frontier also says it will only refund passengers up to $400, so passengers may be paying out of pocket for a more expensive flight.

Finally, the airline says that the deal is available to family members and their spouses — but only if their last name is "Green" or "Greene." Unfortunately, passengers won't be able to count their maiden names.

The deal is only applicable when flights are booked on Frontier's website. For more information, click here.