What is Southwest Airlines' carry-on size limit?

Southwest allows one carry-on bag up to 24 x 16 x 10 inches and one personal item. All reviewed backpacks fit comfortably. Southwest is one of the most lenient US carriers.

Does Southwest charge for carry-on bags?

No. Southwest includes one carry-on and one personal item free on every fare including Wanna Get Away. This is a significant advantage over Spirit and Frontier.

How strict is Southwest Airlines with carry-on sizes?

Southwest is among the least strict US carriers. Size enforcement is very rare. The open seating policy and two free checked bags make Southwest one of the most traveler-friendly US airlines.

Can I use the Peak Design 45L on Southwest Airlines?

Yes. At 22 x 14 x 9-12 inches, the Peak Design fits within Southwest's generous 24 x 16 x 10 inch limit even at fuller expansion levels.

Does Southwest have a carry-on weight limit?

Southwest does not enforce a carry-on weight limit. You must be able to lift your bag into the overhead bin, but there is no official weight cap.

Best Backpack for Southwest Airlines (2026): Complete Size Guide

Photo by Forsaken Films on Unsplash

Southwest is the most generous US carrier for carry-ons. Most 40L travel backpacks fit easily, and you get two free checked bags if needed. Here is how to choose the right one.

Updated March 2026 · 10-minute read · Affiliate disclosure below

Quick Answer

Our pick: The Osprey Farpoint 40 ($111) is the best value for Southwest flights. It fits comfortably despite exceeding the depth limit by 0.1″, which Southwest never enforces. Strong hip belt, proven durability, unbeatable price.

Women’s pick: The Osprey Fairview 40 ($200) offers the same Southwest compatibility with women-specific fit.

Best organization: The Cotopaxi Allpa 35L ($220) has superior internal organization. The 10″ depth exceeds Southwest’s limit but causes no issues in practice.

Southwest’s Carry-On Policy

Carry-on limit: 24″ × 16″ × 10″ (most generous in the US)
Personal item: 18.5″ × 13.5″ × 8.5″
All fares include both (no Basic Economy restrictions)
TWO FREE CHECKED BAGS on all fares
Enforcement: Very lenient – rarely measure bags

Southwest’s generous policy means virtually any 40L backpack works. Gate agents prioritize customer service and rarely enforce dimensional limits.

Our Top Picks

Best Value

Osprey Farpoint 40

Price: $111

Capacity: 40L

Dimensions: 21.3″ × 13.8″ × 9.1″

The Farpoint 40 fits easily within Southwest’s generous 24″ × 16″ × 10″ carry-on limit. At 21.3″ × 13.8″ × 9.1″, it’s well under the size restrictions.

At $111, this offers the best value in travel backpacks. The hip belt transfers weight off your shoulders during long airport walks. Osprey’s reputation for durability means this bag should last for years. The clamshell opening makes packing easier than top-loading designs.

Pros

Best price-to-quality ratio
Hip belt for comfort
Osprey’s lifetime warranty

Cons

Basic organization
No quick laptop access

Read Full Review Check Price on Amazon

Osprey Fairview 40 (Women’s)

Price: $200

Capacity: 40L

Dimensions: 21.3″ × 13.8″ × 9.1″

Perfect for Southwest with women-specific fit: shorter torso range, narrower shoulder straps, contoured hip belt. Osprey recommends this for women 5’–5’8″. Well within Southwest’s generous limits.

Read Review Check Price on Amazon

Cotopaxi Allpa 35L

Price: $220

Capacity: 35L

Dimensions: 20″ × 12″ × 10″

At 20″ × 12″ × 10″, the Allpa fits perfectly within Southwest’s 24″ × 16″ × 10″ limit. Superior organization with multiple internal pockets, compression straps, and a separate shoe compartment. The 35L capacity works well for lighter packers. Cotopaxi is also a certified B-Corporation.

Read Review Check Price on Amazon

Tortuga Travel Backpack Pro

Price: $350

Capacity: 40L

Dimensions: 21″ × 13.5″ × 9″

Fits Southwest’s generous limits with room to spare. Built with 1680D ballistic nylonthe same material used in military gear. This bag should last 10+ years of heavy travel. The tradeoff: at 4.4 pounds empty, it’s heavier than the Farpoint (3.5 lbs) or Allpa (3.3 lbs). Worth it if you travel frequently and want a bag that outlasts everything else.

Read Review Check Price on Amazon

What to Expect at Southwest Gates

Southwest’s customer-first culture extends to baggage:

Every Flight

Gate agents don’t measure bags. Southwest’s generous 24″ × 16″ × 10″ limit means virtually any travel backpack works. Friendly service, no hassles.

Backup Option

If you somehow have issues, remember: Southwest gives you TWO FREE CHECKED BAGS on every fare. No airline in the US offers better baggage policies.

Common Questions

Can I bring a 40L backpack on Southwest?

Absolutely. Southwest has the most generous carry-on limits in the US (24″ × 16″ × 10″). Most 40L backpacks are around 21″ × 14″ × 9″, which fits easily with room to spare.

Does Southwest measure carry-on bags?

Almost never. Southwest’s customer-first culture means gate agents prioritize smooth boarding and friendly service over dimensional enforcement. Their limits are generous enough that most bags fit anyway.

What if overhead bins are full on Southwest?

Gate agents ask for volunteers to check bags. Since Southwest offers two free checked bags on every fare, there’s no fee. Your bag goes to baggage claim (not gate pickup like other airlines).

Why is Southwest so much better for carry-ons?

Southwest’s 24″ × 16″ × 10″ limit is 2″ deeper than most carriers (who use 22″ × 14″ × 9″). They also include two free checked bags on every fare, so they don’t need to generate revenue through baggage fees like other airlines.

About this guide: We aggregate traveler experiences from Reddit’s r/onebag community, FlyerTalk forums, and verified Amazon reviews, cross-referenced with Southwest’s published carry-on policies.

Affiliate disclosure: Carry-On Gear Guide uses affiliate links. If you buy through a link on this page, we may earn a commission at no extra cost to you. This does not influence our recommendations.

Last updated March 8, 2026