Personal Item & Duffel
Luggage & Travel · 8 specs
Direct Answer
Airline personal items must fit underneath the seat in front, standardized to 18 × 14 × 8 inches (45 × 35 × 20 cm) in the US and 40 × 20 × 25 cm on European ultra-low-cost carriers, corresponding to 20–25 liter daypacks and 40–50 liter weekender duffels.
Source: FAA Cabin Safety / Airline Underseat Dimensional Envelopes · Last reviewed Aug 28, 2026
Specs
| Governing Dimension | Underseat stowage envelope (L × W × H) |
| US Major Airline Personal Item (Delta, United, AA) | 18 × 14 × 8 inches (45 × 35 × 20 cm) | ~20–25 L |
| Ryanair Underseat Bag (Free Tier) | 40 × 20 × 25 cm (15.7 × 7.8 × 9.8 in) | 20 L |
| EasyJet Underseat Bag (Free Tier) | 45 × 36 × 20 cm (17.7 × 14.2 × 7.8 in) | 30 L |
| Small Daypack Volume | 15 to 22 Liters | Fits under all commercial airline seats |
| Weekender Duffel (Carry-On Max) | 40 to 50 Liters (20–22 × 11–12 × 10–11 in) |
| Expedition Duffel (Checked Only) | 70 to 120 Liters (26–32 × 15–18 × 14–16 in) |
| Underseat Usable Height Clearance | 8.0 to 9.5 inches (reduced on aisle seats due to entertainment electronics) |
Personal Item & Duffel Bag Size Chart
| Bag Type | Typical Dimensions (L × W × H) | Metric Dimensions | Volume Tier | Airline Placement |
|---|---|---|---|---|
| Underseat Personal Item | 18" × 14" × 8" | 45 × 35 × 20 cm | 20–25 Liters | Underseat storage (free on all carriers) |
| Ryanair Free Small Bag | 15.7" × 9.8" × 7.8" | 40 × 25 × 20 cm | 20 Liters | Underseat storage only |
| Weekender Duffel | 21" × 12" × 10" | 53 × 30 × 25 cm | 40–45 Liters | Overhead bin carry-on |
| Medium Travel Duffel | 25" × 14" × 12" | 63 × 35 × 30 cm | 60–70 Liters | Checked luggage |
| Large Expedition Duffel | 30" × 16" × 15" | 76 × 40 × 38 cm | 90–120 Liters | Checked luggage (Heavy duty PVC) |
Underseat Storage Obstructions & Aisle Seat Caveats
While airlines publish underseat dimensions up to 18 × 14 × 8 inches, physical underseat clearance varies significantly based on aircraft seating architecture:
- In-Flight Entertainment (IFE) Equipment Boxes: On widebody international flights, aisle seats frequently have metal IFE server boxes mounted under the seat floor, reducing width by up to 4 inches (10 cm).
- Soft-Sided Bags vs Hard Shells: Soft-sided canvas or nylon backpacks conform to irregular underseat angles, whereas rigid hardshell briefcases cannot flex past seat support legs.