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Typical size for an under-seat bag (personal item)
Most airlines allow a personal item around this size:
- Length: 16–18 inches (40–46 cm)
- Width: 12–14 inches (30–36 cm)
- Height: 8–10 inches (20–25 cm)
A very common guideline is about 18 × 14 × 8 inches , but exact limits vary by airline.
Bags that usually fit under the seat
- Backpacks (school or daypack size)
- Laptop bags
- Purses or totes
- Small duffel bags
- Slim soft-sided travel bags
Soft-sided bags are best because they can squish slightly to fit under tighter seats.
️ Things that affect under-seat space
- Aircraft type: Smaller planes (regional jets) have less space.
- Seat location: Window seats sometimes have slightly less room due to aircraft structure.
- Seat hardware: Entertainment boxes or life-vest storage can reduce space.
- Bulkhead rows: Often do not allow under-seat storage ; bags must go in the overhead bin
What won’t fit
- Standard carry-on roller bags
- Hard-shell suitcases
- Large hiking backpacks
Those usually need to go in the overhead bin .
Important tip
Even if your bag meets the size limit, airlines may require it to fit fully under the seat , not stick out. If it doesn’t, you might be asked to place it overhead or check it.
In short: aim for a small backpack, laptop bag, or tote under ~18 × 14 × 8 inches to safely fit under most airline seats.