Yes, on American Airlines in 2026, you are permitted to bring one carry-on bag and one personal item (such as a backpack) on almost all flights, including Basic Economy. The carry-on bag must fit in the overhead bin and not exceed 22 x 14 x 9 inches. The personal item—which is where your backpack typically fits—must be no larger than 18 x 14 x 8 inches and must be able to fit completely under the seat in front of you. It is a 2026 "pro-tip" to ensure your backpack isn't "over-stuffed," as gate agents at busy hubs like DFW or CLT may ask you to place it in a sizer if it looks like it won't fit under the seat. If you have both a carry-on and a backpack, you are essentially at your limit; any third item (like a shopping bag or purse) must be consolidated into one of those two bags before boarding to avoid an extra gate-check fee.