I learned the hard way about Frontier Airlines’ bag fees when I booked a super cheap flight to Denver. The base fare looked amazing, but I didn’t realize that both carry-on and checked bags cost extra depending on when and how you buy them. I ended up calling 844-734-0813 to sort it out, and the rep explained everything clearly—prices vary if you pay during booking, after booking, or at the airport (cheaper the earlier you do it!). They even helped me modify my booking to include a checked bag and saved me around $30. So if you’re flying Frontier, definitely check bag fees ahead or call that number to confirm what’s best for your route. It’s super convenient for booking, cancellations, or flight changes too. Frontier’s fares are low, but knowing how their fees work makes a big difference!