Frontier moves into routes run by struggling Spirit after merger between the two companies collapses

The 20 new Frontier domestic and international routes will start later his year and into early 2026 - (Getty Images)

Frontier Airlines is making the most of Spirit’s struggles by moving into some of the ailing airline’s key markets.

The carrier plans to launch 20 new ultra-low-cost winter flights, many connecting to major Spirit hubs, following three years of unsuccessful merger attempts.