Spirit Airlines is shutting down as a business after failing to secure a $500m (£368m) bailout from the Trump administration.
The budget airline was in talks with the US government about a rescue deal which would have saved it from collapse.
But discussions collapsed and the carrier said in an announcement on its website on Saturday that with “great disappointment” the airline had “started an orderly wind-down of our operations, effective immediately”.
Spirit was emerging from its second bankruptcy filing in recent years before the US-Israel war in Iran, but the resulting surge in jet fuel costs pushed it over the brink.
All upcoming flights with Spirit have been cancelled.
In Saturday’s statement, the airline said it would automatically process refunds for any flights purchased through Spirit with a credit or debit card to the original form of payment.
Guests who booked flights via a travel agent should contact the travel agent directly to request a refund.
Compensation for those who booked flights using a voucher, credit, airline points or any other method will be determined at a later date through the bankruptcy court process.
