My 3-Bag Carry-On System: How I Travel With 3 Bags (Without Breaking the Rules)

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I’ve been traveling carry-on only for nearly 15 years, and one of my favorite travel hacks is something I call the 3-bag system.

It’s simple, it’s efficient (and yes, it’s allowed).

Let me explain how it works.

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What Is the 3-Bag Carry-On System?

When I fly, I bring:

• A roller carry-on (goes in the overhead bin)
  
• A personal item bag (sits under the seat)
  
• A third bag: usually a sling, crossbody, or small backpack

That third bag holds my essentials (like my phone, wallet, and passport) so they’re always close by.

My Favorite Types of Bags for This System

Below are my current favorite pieces of luggage for traveling carry-on, when I use the 3-bag system.

These are also the bags I mentioned and demonstrated in my video.

Roller Carry-Ons:

Monos Carry-On

Antler Carry-On (blue hard)

Bric’s Carry-On (blue soft)

Travelpro Carry-Ons

Personal Item Bags:

Nomad Lane Bento Bag

Away Everywhere Bag

Brown Tote Bag

Beige/Light pink duffle

Third bags:

Lo & Sons Crossbody

Quince Crossbody (similar to Lo & Sons but cheaper)

Water Bottle Holder Bag

Lululemon Belt Bag

Belt Bag (cheaper than Lululemon)

Uniqlo Crescent Bag

Why You Need a Third Bag

Even if you’re just traveling for a week or two, you’ll want a smaller bag once you arrive.

Whether it’s for sightseeing, airport transitions, or just peace of mind, this third bag is where I keep:

• Passport and ID
  
• Phone
  
• Credit cards or wallet
  
• Sunglasses, lip balm, earbuds
  
• Anything I’d feel weird not having directly on me

Trying to stash these in pockets or dig through your luggage every time is stressful and impractical, especially at the airport.

But Wait, Aren’t You Only Allowed Two Bags?

Yes. Most airlines only allow:

• One carry-on
  
• One personal item

So how do I bring a third bag without bending the rules?

The Trick: Pack It Away Before Boarding

Before I reach the gate, I:

• Unzip my personal item and tuck my sling or purse inside, or
  
• Slip it into my carry-on if that has more space

🧠 Pro tip: This is why I love top-opening suitcases—much easier than clamshells for this kind of quick access.

Don’t Say You Don’t Have Room

If you’re packing smart, there’s room for this third bag. Because:

• The items in your sling bag (phone, wallet, etc.) are things you’re packing anyway
  
• The sling just acts like a “pouch” or divider. It’s not adding bulk, just structure
  
• And if it takes up too much space, you probably need a better bag setup

Once You’re on the Plane

When I board:

1. I lift my personal item off my carry-on
   
2. I store the carry-on in the overhead bin
   
3. I slide my personal item (with the sling bag tucked inside) under the seat

✅ Done. Two visible bags. Airline rules followed.

Bonus: Most under-seat spaces are more generous than you think.

Once in the air, I can usually pull out my sling and keep it beside my feet (and still be within that one space).

When This Really Comes in Handy

If I’m using a tote as my personal item (like for a beach trip), I don’t want loose items rolling around during the flight.

So I use my sling bag for:

• Lip balm
  
• Tissues
  
• Earbuds
  
• Snacks
  
• Phone

Think of it as your in-flight essentials kit.

Why Hiding a Third Bag Under a Coat Isn’t the Answer

Some travelers wear their crossbody bag and cover it with a jacket.

But here’s the issue: during taxi, takeoff and landing, wearing a bag is a safety hazard.

Because if there’s ever an evacuation, a bag strapped to your body can:

• Get snagged on a seat
  
• Slow you down
  
• Pose a risk to you or others

Flight attendants may ask you to remove it for this reason.

Bonus Tip: Make It Multi-Use

If you’re tight on space, use a sling or crossbody bag that can do double duty.

For example, I often use a padded sling bag (I like this one) as my:

• Tech pouch (for chargers, cords, adapters) during the flight
  
• Sightseeing bag once I arrive

Unpack it at your destination, repack it for the day, and now one bag serves two purposes.