Yes, Frontier Airlines is similar to Spirit, as both of these are ultra-low-cost carriers with a kindred operating model. However, these two air carriers are different from each other in the services they offer to the flyers. When comparing Frontier or Spirit, both provide better perks and are known for budget-friendly flights. But the main differences lie in the flying routes, the fee, and the reliability. If anyone wants to avail more details about the major differences between these two airlines, they can directly contact the customer service of the airline or refer to the blog mentioned earlier.