As if flying weren't stressful enough, what with the long lines, hidden fees, and never-ending delays, these days just figuring out how you're going to afford to buy a ticket home can seem impossible. United will soon make a change that could help out with that. Yesterday, it announced new “basic economy” fares that are more in line with what low-cost airlines like Southwest or Spirit charge. The only catch: Lowest-fare passengers will be limited to one carry-on bag — one that must be small enough to fit under the seat in front of you. That's right. No more squeezing your overstuffed suitcases into the overhead bin. This new rule is part of the airline's new fare initiative called Basic Economy. In addition to only being allowed one small carry-on, Basic Economy travelers will not have their seats assigned until right before boarding the plane. This means travelers who purchased their tickets together aren't guaranteed to be seated next to one another. Basic Economy travelers will be required to board the plane last and won't be eligible for upgrades. The Huffington Post reported that this change is expected to add $1 billion dollars to United's annual earnings by 2020, which makes sense because more travelers will now be choosing to pay to check bags, or will select higher fares that allow for more carry-ons. Julia Haywood, United’s chief commercial officer, wrote in a press release, “Customers have told us that they want more choice, and Basic Economy delivers just that. By offering low fares while also offering the experience of traveling on our outstanding network, with a variety of onboard amenities and great customer service, we are giving our customers an additional travel option from what United offers today." The airline will continue to offer economy, Economy Plus and domestic first class.