Topo Designs’ Carry-On Bag Size Guide

The perfect carry-on bag size lets you glide onto the plane with your essentials by your side. The wrong size can mean battling for overhead bin space—or getting fines from the airline, if you exceed their size limits.

When you're planning the perfect trip, you don't want to waste time deciphering different airlines’ varied requirements for carry-on luggage sizes. Below, we break down the basics, highlighting airline carry-on dimensions for popular carriers in the United States.

Carry-On Dimensions by Airline

Whether you want something small enough to stash under the seat or need a compact weekender for quick getaways, Topo's travel gear has you covered with a variety of versatile travel bags.

Here's a breakdown of carry-on bag size limits:

• Alaska Airlines: 22 x 14 x 9 inches¹
• American Airlines: 22 x 14 x 9 inches²
• Delta Airlines: 22 x 14 x 9 inches³
• Frontier Airlines: 22 x 16 x 9 inches⁴
• JetBlue Airlines: 22 x 14 x 9 inches⁵
• Southwest Airlines: 24 x 16 x 10 inches⁶
• United Airlines: 22 x 14 x 9 inches⁷

Note that the dimensions listed include any handles and/or wheels the bag may have. The Apex Global Travel Bag Roller fits the requirements of all the above airlines. The Global Travel Bag Roller and Global Travel Duffel are made to move with ease, so there’s no second-guessing at the gate.

If you prefer using a backpack, you’re in luck. Our Global Travel Backpack and Global Travel Bag 30L fit within most airline carry-on guidelines and have plenty of space for modern travel essentials and come equipped with organization features that make packing easier.

Personal Item and Underseat Backpacks

In addition to a carry-on bag, most airlines also allow a small personal item, like a purse or laptop bag. As a rule, the personal item must fit under the seat in front of you. Here's a rundown of airline carry-on dimensions for personal items:

• Alaska Airlines: Passengers are allowed to have one personal item, such as a purse, briefcase, or laptop bag¹
• American Airlines: Personal items cannot exceed 18 x 14 x 8 inches²
• Delta Airlines: Passengers can bring one personal item that fits under the seat in front of them, such as a purse, laptop bag, or similar³
• Frontier Airlines: Personal items cannot exceed 18 x 14 x 8 inches⁴
• JetBlue Airlines: Personal items cannot exceed 17 x 13 x 8 inches⁵
• Southwest Airlines: Personal items must go under the seat. Southwest also considers blankets and pillows to be personal items⁶
• United Airlines: Personal items cannot exceed 17 x 10 x 9 inches⁷

Topo has a number of smaller bags that can fit under a standard airline seat. Try a tote bag ,like the Mountain Essential Tote or Mountain Utility Tote for a quick weekend city trip . If you're planning a more active adventure, opt for one of our smaller backpacks, such as the Rover Pack Classic 20L. The Global Briefcase and Apex Global Briefcase are ideal for business travel or a working vacation.

Checked Bag Options

If you're going on a longer trip, you'll want to check a bag. Checked baggage allowances are more generous than carry-on bag size restrictions. For example, United allows checked bags of up to 30 x 20 x 12 inches7.

A roller bag or duffel can be a good choice for that extra space you need. Get the best of both worlds with one of our roller bags. If a longer trip is on the calendar, the Mountain Duffel—with a generous 40L capacity—was made for you.

Choosing the Right Size for Your Travel Bag

Here are some factors to consider when selecting a travel bag:

• Length of trip: Are you going away for a weekend? A week? A month? How long you'll be gone—and your access to laundry facilities—will influence your space needs.
• Activities: What will you be doing where you're headed? If you're going to be hiking, a backpack is a good pick. Planning on a lot of shopping? A tote bag might suit you better.
• Extra space needs: Speaking of shopping, will you be buying things on your trip? Keep in mind that you might need to leave space in your luggage for souvenirs. Stash the Peakview Packable Backpack in your main bag to carry as a daypack and hold extras on your trip back home.

No matter where your next trip takes you—or why you’re traveling—count on Topo Designs to protect your belongings. We prioritize durable materials, ample storage, and bag organization options to make every adventure a breeze.

FAQ

What size bag fits under a seat?

A bag should not exceed 18 x 14 x 8 inches to fit under an airline seat. These are the measurements most airlines use to qualify a bag as a personal item.

Can a 40L backpack be a carry-on?

Yes, a 40L backpack will meet most airlines’ sizing requirements for carry-on bags. However, check with the specific airline to confirm what size backpack fits under an airplane seat.

Are Topo bags TSA-approved?

Many Topo bags are made to fit carry-on guidelines, so they can keep up with every adventure. Be sure to compare your airline’s restrictions and your bag’s dimensions to be sure carry-ons and personal items will fit.

Sources:

1. Carry-on Luggage. Alaska Air. Retrieved November 25, 2025, from https://www.alaskaair.com/content/travel-info/baggage/carry-on-luggage
2. Carry-on Bags. American Airlines. Retrieved November 25, 2025, from https://www.aa.com/i18n/travel-info/baggage/carry-on-baggage.jsp
3. Carry-on Baggage. Delta. Retrieved November 25, 2025, from https://www.delta.com/us/en/baggage/carry-on-baggage
4. What are the Sizes and Weight Limits for Bags? Fly Frontier. Retrieved November 25, 2025, from https://faq.flyfrontier.com/help/bags-seats-general-info-what-are-the-sizes-and-weight-limits-for-bags
5. Carry-on Bags. JetBlue. Retrieved November 25, 2025, from https://www.jetblue.com/help/carry-on-bags
6. I Want to Know About the Carryon & Personal Items Policy. Southwest. Retrieved November 25, 2025, from https://support.southwest.com/helpcenter/s/article/carryon-baggage-policy
7. Carry-on Bags. United. Retrieved November 25, 2025, from https://www.united.com/en/us/fly/baggage/carry-on-bags.html