Is a Backpack a Carry-On or Personal Item? Travel Rules Explained

The one‑minute answer

• If your backpack fits under the seat, it usually counts as a personal item. Airlines describe personal items as smaller bags—purses, briefcases, laptop bags, small backpacks—that must fit beneath the seat in front of you.
• If your backpack goes in the overhead bin, it’s treated as a carry‑on and must meet that airline’s size rules (most U.S. carriers use 22″ × 14″ × 9″; Southwest allows up to 24″ × 16″ × 10″).
• On most full‑service U.S. airlines you can bring one carry‑on + one personal item for free; some Basic Economy fares (notably United) exclude a free overhead‑bin carry‑on and allow only a personal item.

• Carry‑on: Larger cabin bag placed in the overhead bin. Typical U.S. maximum is 22 × 14 × 9 in (including wheels/handles). Southwest allows up to 24 × 16 × 10 in. You’ll still need to lift it unassisted.
• Personal item: Smaller piece that must fit under the seat. Examples include small backpacks, briefcases, and laptop bags. Airlines publish under‑seat max dimensions (varies by carrier and aircraft).

• American: 18″ × 14″ × 8″.
• United: 9″ × 10″ × 17″.
• JetBlue: 17″ × 13″ × 8″.

Is a backpack a carry‑on or personal item? (Decision flow)

1. Measure your backpack (length × width × height, fully packed).
2. Compare to your airline’s under‑seat limit (if ≤ under‑seat limit → personal item). Examples above: AA 18×14×8, United 9×10×17, JetBlue 17×13×8.
3. If it’s larger than the under‑seat limit but within the overhead limit (commonly 22×14×9, Southwest 24×16×10), it’s your carry‑on.

What about Basic Economy?

• United Basic Economy: Personal item only on most routes. A larger backpack that needs the overhead bin isn’t included and may be charged/gate‑checked.
• American Basic Economy: Includes one carry‑on + one personal item (so a backpack can be either, depending on size).
• Delta Main Basic (Delta’s name for Basic Economy): still 1 carry‑on + 1 personal item; overhead space can be limited on regional jets.
• JetBlue: All fares include a personal item; since Sept. 6, 2024, Blue Basic also includes a carry‑on (space permitting).

Quick airline cheat sheet (U.S.)

How to choose the right backpack for your fare and route

1. Aim for “under‑seat” if you booked Basic Economy on United. If your backpack is ≤ that airline’s personal‑item limit (e.g., United 9×10×17), you’re covered; anything larger can trigger fees or a gate check.
2. Flying a full‑service fare (American/Delta/United standard, JetBlue)? You can normally bring both: your carry‑on (overhead) and a personal‑item backpack (under seat). If your backpack is larger, let it be the carry‑on and pair it with a slim under‑seat pouch as your personal item.
3. On Southwest, overhead limits are more generous (24×16×10). A mid‑size backpack often fits as a carry‑on as long as it stays within those dimensions.
4. Regional jets/short‑haul flights. Overhead bins may be smaller; even standard 22×14×9 carry‑ons can be gate‑checked. Keep a slim under‑seat backpack for essentials. (Delta notes restricted bin space on some Connection flights.)

Measuring & packing tips (so your backpack passes the sizer)

• Measure “packed” size (not empty). Soft packs can balloon—measure after you load it.
• Keep it rectangular. Use pouches or a small packing cube to avoid bulges that break the sizer.
• Put dense items at the bottom if it’ll ride overhead; if it’s your under‑seat personal item, put dense items toward the back panel so it slides under the seat neatly.
• Laptop + liquids ready. Most airlines still want laptops and 3‑1‑1 liquids accessible at screening; keep them in top pockets to avoid repacking at security. (Delta summarizes common 3‑1‑1 guidance.)

Real‑world examples: backpacks by size

• 15–18L daypack (compact “city” pack): Often qualifies as a personal item on U.S. airlines if its packed dimensions stay within under‑seat limits (e.g., AA 18×14×8, JetBlue 17×13×8, United 9×10×17—United’s height/depth are the tightest).
• 20–30L travel pack: Frequently treated as a carry‑on; check you’re within 22×14×9 (or 24×16×10 on Southwest).
• 35L+ hiking/trekking packs: Typically too large for personal‑item status and may exceed carry‑on size if long/tall; plan for overhead (if within dimensions) or to check the bag where required. (Confirm your route—international and budget carriers can be stricter on weight/size.)

Gate‑agent realities (and how to avoid hassles)

• Consistency varies. Airlines publish clear rules, but bins fill up and crews prioritize larger roller bags in overheads. Keep your personal‑item backpack under the seat unless invited to use overhead space.
• Boarding order matters. Basic Economy boards later; the bins may be full by then. If your backpack is your carry‑on, have a plan to gate‑check or keep valuables in a smaller pouch you can remove quickly.
• Budget carriers check sizes closely. Frontier and Spirit explicitly note that oversized personal items are chargeable; use their sizers to verify.

How to pack a backpack so it counts as a personal item

1. Keep the height slim. United’s 9″ × 10″ × 17″ limit is especially tight—pack flatter items against the back panel and avoid thick shoes inside the pack.
2. Use compression lightly. Over‑stuffing can push your bag past under‑seat limits; compression straps should square the bag, not bulge it.
3. Wear the bulkiest layer. A jacket or hoodie on your body can save an inch or two in your pack.
4. Choose flexible materials. Soft nylon packs “give” into the under‑seat space better than rigid frames.

A note on overhead maximums

“Is backpack a carry on?” vs “Is a backpack a personal item?” — choosing on purpose

• If you want hands‑free boarding and zero bin competition, target a personal‑item backpack under the airline’s under‑seat limits (e.g., 18×14×8 on AA, 17×13×8 on JetBlue, 9×10×17 on United).
• If you need more capacity, let your backpack be the carry‑on (overhead) and add a small under‑seat pouch as your personal item. Delta/American allow both on standard fares; United’s Basic Economy does not include a free overhead carry‑on.

How the 16L daypack fits into airline rules (practical example)

Frequently Asked Questions