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Southwest Personal Item Size Requirements 2026

Every Southwest passenger gets one personal item in addition to their carry-on bag - completely free. This comprehensive guide covers the official size limits, what qualifies as a personal item, and how to maximize this valuable free allowance.

Personal Item Size Specifications

Official Dimensions

18.5" × 8.5" × 13.5"

Length

18.5 inches

Width (Depth)

8.5 inches

Height

13.5 inches

Must fit: Completely under the seat in front of you
Location: Between your feet and the seat in front
Cannot: Be placed in overhead bins (that's for carry-on bags)

What Qualifies as a Personal Item?

Southwest defines a personal item as a smaller bag that fits under the seat. Here are common examples that meet the size requirements:

Acceptable Personal Items

  • Purse or handbag (most sizes)
  • Small backpack (school/day pack size)
  • Laptop bag or briefcase
  • Tote bag (small to medium)
  • Diaper bag
  • Camera bag
  • Small duffel bag
  • Messenger bag
  • Lunch box or food container
  • Small cooler (soft-sided)

Items Too Large for Personal Item

  • Large hiking backpacks (40L+)
  • Rolling suitcases (these are carry-ons)
  • Large sports duffels
  • Oversized purses (over 18.5")
  • Large camera cases (professional gear)
  • Full-size garment bags
  • Musical instruments in cases (most)
  • Duty-free shopping bags (too big)

Personal Item vs Carry-On Bag

Understanding the difference between your personal item and carry-on bag helps you maximize your free allowance on Southwest flights.

FeaturePersonal ItemCarry-On Bag
Maximum size18.5" x 8.5" x 13.5"10" x 16" x 24"
Storage locationUnder seat in front of youOverhead bin
CostAlways FREEAlways FREE
Typical itemsPurse, backpack, laptop bagRoller bag, large backpack
Weight limitNone (must lift yourself)None (must lift yourself)
AccessibilityEasy access during flightHarder to access in-flight

How to Measure Your Personal Item

Step-by-Step Measuring Guide

  1. 1

    Measure the Length

    Longest side of your bag - typically from bottom to top when standing upright. Must be ≤ 18.5 inches.

  2. 2

    Measure the Width/Depth

    Front to back measurement. Must be ≤ 8.5 inches. This is usually the narrowest dimension.

  3. 3

    Measure the Height

    Side to side when standing. Must be ≤ 13.5 inches.

  4. 4

    Include All External Features

    Pockets, straps, and handles count toward total dimensions.

  5. 5

    Test Under Your Seat at Home

    Try sliding it under a chair. Personal items need to fit completely under the aircraft seat.

What to Pack in Your Personal Item

Your personal item should contain items you'll need during the flight or immediately upon arrival, since it stays at your feet for easy access.

Flight Essentials

  • • Laptop or tablet
  • • Phone charger and headphones
  • • Book or e-reader
  • • Travel documents and ID
  • • Medications (prescription and OTC)
  • • Snacks and empty water bottle
  • • Wallet and credit cards
  • • Hand sanitizer and wipes

Comfort Items

  • • Neck pillow (inflatable saves space)
  • • Light jacket or sweater
  • • Eye mask and earplugs
  • • Tissues and hand lotion
  • • Gum or mints
  • • Change of clothes (for long trips)
  • • Toiletries (following TSA 3-1-1 rule)
  • • Entertainment (cards, puzzles)

Maximizing Your Personal Item Space

Smart Packing Strategies

  • Use a Backpack Instead of a Purse

    Backpacks can be larger while still fitting under the seat. Switch from a purse to a small backpack to nearly double your capacity.

  • Fill Every Pocket

    Utilize all compartments, including outside pockets, to maximize space without exceeding dimensions.

  • Pack Soft Items

    Clothing and soft goods compress easily. Pack a change of clothes in your personal item as backup.

  • Use Packing Cubes

    Small packing cubes keep items organized and maximize every inch of your personal item.

Items That Don't Count Against Your Allowance

Certain items can be brought on board in ADDITION to your carry-on bag and personal item without counting against your allowance.

Free Additional Items

  • Jacket, coat, or hat
  • Umbrella (standard size)
  • Reading material
  • Food for the flight
  • Assistive devices
  • Child car seat or stroller
  • Pillow or blanket
  • Duty-free purchases (sealed bags)

Traveling With Only a Personal Item

For short trips, you can skip the carry-on bag entirely and travel with just a personal item. This saves overhead bin space and lets you board quickly.

Personal Item-Only Travel Tips

  • Weekend trips: 2-3 days of clothes easily fits in a large backpack
  • Business travel: One suit, shirts, and laptop fit in a slim backpack
  • Toiletries: Use solid alternatives or hotel amenities
  • Laundry: Plan to wash clothes if staying longer
  • Wear bulky items: Jacket, boots on the plane to save space
  • Ship ahead: Send extra items to your hotel in advance

Common Questions About Personal Items

Does Southwest actually measure personal items?

Southwest rarely measures personal items unless they're obviously oversized. As long as your item fits under the seat in front of you without blocking the aisle or taking up too much space, you'll be fine. The 18.5" x 8.5" x 13.5" dimensions are generous.

Can I bring two personal items if I don't have a carry-on?

No. You're limited to ONE personal item plus ONE carry-on bag, for a total of two items. You cannot bring two personal items even if you skip the carry-on. However, items like jackets, umbrellas, and reading material don't count against this limit.

What if my purse is slightly larger than 18.5 inches?

Southwest is generally flexible with purses and small bags as long as they fit under the seat. A purse that's 19-20 inches will likely be fine if it's soft-sided and can compress. Rigid bags that exceed the limit are more likely to be challenged.

Can I put my personal item in the overhead bin?

Technically yes, but it's not recommended. Personal items are meant to go under the seat so you have easy access during flight. Using overhead bin space for a personal item when you also have a carry-on may frustrate other passengers and flight attendants.

Does my laptop bag count as my personal item or can I bring it plus a purse?

You get ONE personal item total. If you have both a laptop bag and a purse, you'll need to consolidate them into one bag, or use one as your personal item and the other as your carry-on. Many travelers use a backpack that holds both their laptop and personal items.

Are diaper bags considered personal items?

Yes, diaper bags count as your one personal item. However, Southwest is generally accommodating to parents with young children. Some gate agents may allow small diaper bags in addition to a personal item, especially if you're traveling with an infant, but this isn't guaranteed.

Plan Your Southwest Packing Strategy

Maximize your free personal item and carry-on allowance to avoid checked baggage fees. Use our calculator to see if checking bags makes sense for your trip or if you can travel with carry-on only.

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