Introduction

Navigating air travel today isn’t just about picking the right flight — it’s also about making sure your bags meet airline regulations. And when you’re flying United Airlines, knowing the carry-on size policy ahead of time can save you from unexpected fees and frustrating gate delays. Whether you’re a frequent flyer or a first-time traveler, understanding United Airlines’ carry-on rules is essential for a smooth journey.

United Airlines is one of the largest carriers in the U.S., flying to more than 300 destinations globally. As such, its baggage policy affects millions of passengers every year. Many travelers are caught off guard by strict enforcement of bag size regulations, especially for carry-ons and personal items. That’s why it’s crucial to get familiar with these rules before you pack.

From standard dimensions to special allowances and what qualifies as a personal item, this guide will walk you through every detail of United Airlines’ carry-on size policy. It’ll help you avoid surprises at the gate and make sure your journey begins without a hitch.

What is United Airlines' Carry-On Size Policy?

United Airlines allows one carry-on bag and one personal item per passenger, but both must meet specific size criteria. These dimensions are strictly enforced, particularly during boarding.

Here’s a breakdown of United’s current policy for United Airlines carry on bag size:

Maximum size for carry-on bag:
22 x 14 x 9 inches (56 x 35 x 23 cm) including wheels and handles.
Maximum size for personal item:
17 x 10 x 9 inches (43 x 25 x 22 cm).
Weight limit:
United does not have a specific weight limit for carry-on bags, but you must be able to lift it into the overhead bin unassisted.
Allowed for most ticket types:
Carry-on bags are allowed for all fare classes except Basic Economy (domestic).

This policy applies to both domestic and international flights operated by United, though certain partner airlines may have slightly different rules.

Also, items like umbrellas, reading material, and duty-free purchases do not count as your personal item or carry-on — giving you a bit more leeway when packing smartly.

Personal Item vs. Carry-On: What’s the Difference?

One of the most common points of confusion is the distinction between a carry-on bag and a personal item. While both are brought onboard, they serve different purposes and go in different storage spaces.

Carry-On Bag:

Goes in the overhead bin.
Larger in size.
Common examples: roller suitcase, duffel bag, larger backpacks.

Personal Item:

Must fit under the seat in front of you.
Smaller in size.
Common examples: laptop bag, purse, briefcase, small backpack.

Accepted Personal Items Include:

Tote bags
Diaper bags
Camera bags
Slim briefcases
Laptop cases

Not Allowed as Personal Items:

Larger roller bags
Gym bags
Oversized backpacks

United may enforce personal item sizes more strictly in crowded flights or limited-seating aircraft. Always test your bag in their sizer if you’re unsure — gate agents often do random checks.

Detailed Size and Weight Limits

Understanding the exact limitations can be the difference between breezing through the gate or being forced to check your bag — and pay extra for it.

Carry-On Bag Dimensions

United Airlines defines the maximum size for carry-on bags as:

22 inches long
14 inches wide
9 inches high

This includes handles, wheels, and any side pockets. If your bag bulges due to overpacking or has non-retractable handles, it may be flagged as oversized. United provides size check bins near most gates — it’s worth testing your bag before boarding.

Personal Item Dimensions

Personal items must be smaller and fit underneath the seat in front of you. The size limit is:

17 inches long
10 inches wide
9 inches high

This space can be especially tight if you're seated on smaller regional jets, so packing thin and compact is crucial.

Weight Limit Policy

Interestingly, United does not impose a strict weight limit for carry-on or personal items. However:

You must be able to lift the bag into the overhead bin without help.
Heavy or clumsy items may be redirected to checked baggage if they cause boarding delays or safety concerns.

This policy offers flexibility, but be mindful — heavy doesn’t mean unlimited. Excessively heavy bags might draw attention from gate staff.

Exceptions to the Carry-On Policy

There are certain situations where the carry-on rules are more flexible. United Airlines makes some exceptions for passengers traveling with specific needs or under unique circumstances.

Travel with Infants

Parents flying with infants can bring additional items beyond the regular carry-on allowance:

Diaper bag
Breast pump and milk (considered medical devices)
Small cooler for baby food
Car seat or stroller (usually gate-checked for free)

These items do not count toward your standard carry-on or personal item limit.

Medical Assistive Devices

United Airlines allows passengers to bring the following items in addition to their carry-on and personal item:

Wheelchairs
Crutches
Canes
CPAP machines
Portable oxygen concentrators

These are not counted as carry-ons and do not incur extra fees, but they must meet FAA safety standards.

Duty-Free Items and Special Purchases

If you’re traveling internationally and purchased duty-free items at the airport, they won’t count against your baggage allowance. Just make sure the bag seals properly and contains only the items purchased.

United Basic Economy Carry-On Rules

When flying United Airlines on a Basic Economy ticket, the carry-on baggage rules get much stricter. This is one of the most misunderstood parts of United’s baggage policy, so let’s break it down carefully.

Here’s what Basic Economy passengers are allowed:

One personal item only (must fit under the seat).
NO carry-on bag allowed in the overhead bin — unless you meet one of the exception categories.

Allowed Personal Items:

Laptop bags
Shoulder bags
Small backpacks
Tote bags

If you attempt to bring a standard carry-on bag with a Basic Economy fare, it will be checked at the gate and a fee of $35 to $45 may apply, depending on the route. Plus, you may wait longer at baggage claim.

Exceptions Where Carry-Ons Are Allowed in Basic Economy:

Premier® members (MileagePlus elite tiers)
Star Alliance™ Gold members
Primary cardholders of qualifying MileagePlus credit cards
Passengers on transatlantic or transpacific international flights

In these scenarios, the carry-on policy reverts to the standard one, and passengers may use the overhead bins as usual.

Tip: If you’ve booked Basic Economy but plan to bring a carry-on, consider upgrading at check-in. United often offers affordable upgrades that include full-size carry-on privileges.

Luggage That Meets United Airlines Requirements

Getting a carry-on bag that perfectly aligns with United’s size restrictions is essential. Otherwise, you’ll end up checking your bag at the gate — and possibly paying extra for it.

Recommended Luggage Brands and Models

Here are some popular carry-on options that comply with United’s 22 x 14 x 9 inches limit:

Travelpro Platinum Elite 21” Expandable Spinner
Samsonite Winfield 3 DLX Hardside Luggage
Briggs & Riley Baseline Domestic Carry-On
Away The Bigger Carry-On (double-check size for wheels)
Amazon Basics Hardside Spinner 20-Inch

Before purchasing a bag, always confirm the total dimensions (including wheels and handles), not just the internal compartment size.

Tips to Measure Your Bag Correctly

Measuring your bag at home is simple if you follow these steps:

Set the bag upright on a flat surface.
Measure from the bottom of the wheels to the top of the handle (when retracted).
Measure side-to-side including external pockets.
Record the front-to-back depth, including handles or zippers.

Use a soft tape measure and write down each number. Compare it to United’s carry-on limit of 22 x 14 x 9 inches. If any measurement exceeds, be prepared for gate checking.

Pro tip: Soft-sided bags offer more flexibility in tight sizers than hard-shell models.

Overhead Bin Space and Boarding Process

Ever boarded a plane and found no room for your carry-on in the overhead bin? That’s a real concern, especially with full flights and more people bringing bags onboard.

How Boarding Groups Affect Bin Space

United’s boarding process involves groups — from Group 1 to Group 5, and even pre-boarding for select passengers. The earlier your boarding group, the better your chance to find overhead space.

Group 1: Premier 1K, Premier Platinum, First Class
Group 2: United credit card holders, Premier Silver
Group 3–5: Economy customers, ranked by seat location and fare type

Late boarding (Group 4 or 5) often means bins are full. In that case, United may gate-check your bag for free, but that adds time at baggage claim and risk of loss/damage.

Tips to Ensure Overhead Bin Access:

Check in early to get a better boarding group.
Use United's mobile app to manage upgrades or boarding perks.
Travel light — if you can keep your bag below the seat, you avoid the bin hassle.

Gate agents are also trained to remove bags that are too large or are taking up excessive space. So, even if you board early, make sure your bag fits upright.

Carry-On Policy for International Flights

Flying internationally with United? The good news is the carry-on size limits remain the same, regardless of your destination. But there are a few things you should know.

Standard Carry-On Policy Applies Globally

No matter if you’re flying to Tokyo, London, or São Paulo — the allowed carry-on and personal item sizes are:

Carry-on: 22 x 14 x 9 inches
Personal item: 17 x 10 x 9 inches

This makes it easier to pack consistently, especially if you're connecting through multiple airports.

International Basic Economy Includes Carry-On

Unlike domestic Basic Economy, international Basic Economy fares typically allow:

One personal item
One carry-on bag

However, this only applies to transatlantic and transpacific flights. If you're connecting within the U.S. on a domestic leg, the domestic rules may apply unless your fare includes the carry-on.

Regional Partners and Star Alliance Connections

If part of your itinerary includes flights with regional partners or Star Alliance airlines (e.g., Lufthansa, ANA, Swiss Air), their carry-on rules might be slightly different.

Some allow only 18 x 14 x 8 inches
Others have strict weight limits (7 kg or 15 lbs)

Tip: Always check with all airlines on your ticket to avoid a bag that’s compliant with United but rejected by your next flight.

United Airlines' Carry-On Bag Policy: Avoid Extra Fees