Domestic carry-on policies. A good rule of thumb is that if your carry-on bag fits under the seat in front of you, it's considered a personal item. This includes small backpacks, purses, briefcases, laptop bags, etc. Larger bags, including suitcases, must fit in the overhead bin compartment.

Yes, a mini backpack can almost always be used as a personal item in 2026, provided its dimensions do not exceed the airline's specific "under-seat" requirements. Most major carriers like Delta, United, and American Airlines allow personal items up to 18 x 14 x 8 inches, which a standard "mini" backpack (like those from Loungefly or Fjällräven Kånken Mini) easily fits within. Even on ultra-low-cost carriers like Spirit, Frontier, or Ryanair, which are notoriously strict, a mini backpack is the "pro" traveler's secret weapon for avoiding baggage fees. These bags typically measure around 10 to 12 inches in height, leaving plenty of room for your feet even when tucked under the seat. However, be cautious not to "over-stuff" the bag so that it bulges; if it cannot fit into the airline's sizing metal bin at the gate, they may classify it as a carry-on and charge you an expensive "gate-check" fee. As long as it sits comfortably under the seat in front of you, it is the perfect compliant personal item for 2026 travel.