The feeling is all too common. You’re in the airport security line, your 40L backpack (your only piece of luggage) is on the conveyor, and that moment of doubt hits. Did I forget the sunscreen at the bottom? Is my toothpaste tube too big?
That small-scale panic as you rummage for your clear plastic bag is one of the most stressful parts of modern travel. It’s a process I decided to eliminate years ago.
After obsessively refining my one-bag travel system for nearly five years, I’ve found the real secret isn’t just managing liquids—it’s eliminating them. My work with ‘Travel with dp’ has always been about sharing practical, repeatable systems that make travel simpler. This is my most important one: the solid-state toiletry kit that makes security a complete non-issue. It’s the key to walking through security with confidence every single time.
First, What Exactly Is the 3-1-1 Liquid Rule?
Before we can bypass the rule, we need to know exactly what it is. It’s simple, but the details are what trip people up. The rule is easy to remember as 3-1-1:
- 3: All liquids must be in travel-sized containers of 3.4 ounces (100 milliliters) or less.
- 1: All containers must fit into one (1) clear, quart-sized (or 1-liter) re-sealable bag.
- 1: Only one (1) bag is allowed per passenger.
This rule exists for security reasons, and it’s enforced globally. The single biggest mistake I see travelers make is thinking a half-empty 200ml bottle is okay. It’s not. Security agents don’t care how much liquid is in the bottle; they only care about the size of the container.
This rule applies to anything with a liquid, gel, or aerosol consistency. Think creams, pastes, and yes, even things like peanut butter or honey.
The Core Strategy: Stop Packing Liquids
For years, my goal was to find the perfect 100ml bottles. I tried dozens, and they all had a problem: they leaked, they were hard to fill, or I’d run out of shampoo on a 10-day trip.
The real “aha!” moment was when I realized I was solving the wrong problem. The goal shouldn’t be to manage liquids; it should be to not bring them at all.
By switching to solid toiletries, you don’t just “beat” the 3-1-1 rule. You make it completely irrelevant.
Here’s why this became the cornerstone of my minimalist travel philosophy:
- No Leaks: A shampoo bar cannot explode at 30,000 feet. A solid lotion bar won’t ooze over your clothes.
- No Security Scramble: Your toiletry bag stays in your backpack. You don’t have to pull anything out for the security bin. This alone is worth it.
- More Space & Less Weight: Solids are incredibly concentrated. A shampoo bar lasts 2-3 times longer than a 100ml bottle, taking up less space and weighing less.
- Long-Term Use: You don’t have to worry about running out. A single bar can last me months of travel.
My Tested Solid Swaps: Building Your TSA-Proof Kit
Going solid doesn’t mean sacrificing quality. In my experience, these products often work better than their liquid counterparts. Here’s a breakdown of my entire solid kit, tested across dozens of trips.
Solid Shampoo & Conditioner Bars
This is the biggest and best swap you can make.
- My Experience: I was skeptical. I thought they would be like a basic bar of soap and strip my hair. The first one I tried did exactly that because it was a “cold-process” soap, not real shampoo. The trick is finding a “surfactant-based” bar, which is essentially liquid shampoo with the water removed.
- How They Work: You either lather the bar in your hands or rub it directly on your wet hair a few times. It explodes into a rich lather just like the liquid stuff.
- Pro-Tips:
- Storage is Key: This is the most important part. A solid bar must dry out between uses, or it will turn to mush.
- Avoid Sealed Tins: Most people buy a metal tin. This is a mistake. It seals in moisture.
- The Solution: I use two things. First, I pat the bar dry with my towel after use. Second, I store it in a “sisal soap bag.” This is a little mesh bag that exfoliates, helps the bar lather, and (most importantly) lets me hang it from a hook to dry completely.
Toothpaste Tablets & Powders
This swap feels the weirdest at first, but it’s the one I appreciate most.
- My Experience: The first time I bit into a tiny, chalky tablet, I was not impressed. But then I started to brush, and it foamed up perfectly. The clean feeling was identical to regular paste.
- Why They’re Better: The real benefit is portion control. For a 10-day trip, I pack 20 tablets (plus a few extra). That’s it. It’s a tiny, weightless packet. No more rolling a tube, no more worrying if my “travel-sized” tube is too big (some are over 100ml!).
- Pro-Tip: I keep a few in my carry-on pocket or sling bag. It’s great for a quick brush on a long-haul flight or during a layover without pulling out my whole kit.
Solid Soap Bars (For Body & Face)
This is an easy one, but you can optimize it. Forget the plastic travel soap case that gets slimy.
- My Experience: I don’t pack two bars (one for face, one for body). That’s not minimalist. I find one high-quality, multi-purpose bar. A simple goat’s milk soap or a pine tar soap works for everything.
- Pro-Tip: Just like the shampoo bar, I use a sisal soap bag. This one stays in the shower. It stops the bar from sitting in a puddle and melting away.
Deodorant (The Easy Win)
Most of us already use a solid stick deodorant. This is an easy win. Just double-check what you’re packing. Many “gel” or “roll-on” deodorants are considered liquids by security. A classic solid stick is not.
Other Solid Swaps: The Next Level
Once you have the basics, you can optimize even further.
- Solid Lotion Bars: These are fantastic for dry climates or post-flight. They look like a bar of soap and are made of butters and oils. You warm it in your hands and rub it on. No greasy bottles.
- Sunscreen Sticks: A total game-changer for one-bag travel. A solid face sunscreen stick and a larger body stick mean I don’t have to buy a bottle at my destination or worry about the 100ml rule.
- Solid Cologne/Perfume: These come in small tins and are wax-based. You rub a small amount on your pulse points. They last forever and have zero spill risk.
My Verdict: Liquid vs. Solid Toiletries
After years of testing, here’s the simple breakdown I use to explain my kit. This isn’t lab data; it’s just my honest experience from the road.
| Item | Liquid Version (The Hassle) | Solid Version (The Solution) | My Personal Takeaway |
| Shampoo | 100ml bottle. Lasts 1-2 weeks. Risk of leaks. | Shampoo Bar. Lasts 2-3 months. No leaks. | The bar is a clear winner. Just need a way to dry it. |
| Toothpaste | 1.5oz tube. Hard to get all out. Messy cap. | Toothpaste Tablets. Precise portions. No mess. | Tablets are strange for two days, then you’ll never go back. |
| Body Wash | 100ml bottle. Gets slimy. Runs out fast. | Bar Soap. Lasts forever. Multi-purpose. | A simple bar in a sisal bag is the most efficient system. |
| Lotion | 100ml bottle. Greasy. Can leak. | Lotion Bar. No mess. Very concentrated. | Great for dry hands on the plane. A “nice-to-have.” |
| Sunscreen | 100ml bottle. Never enough for a beach trip. | Sunscreen Stick. Easy to apply. Not a liquid. | A stick for the face and a larger one for the body is essential. |
What About the Liquids You Must Bring?
I’ll be honest: my kit isn’t 100% liquid-free. There are 2-3 items I haven’t found a solid replacement for (like my contact lens solution or a specific face serum).
This is where the 3-1-1 rule comes back, but now it’s incredibly easy.
Instead of fighting to fit 10 bottles in one bag, I’m fitting two. This is where I optimize the containment system.
Choosing the Right 100ml Reusable Bottles
I’ve had cheap plastic bottles burst under pressure. Don’t be me. If you must bring a liquid, invest in good bottles.
- Get Silicone: I look for wide-mouth, squeezable silicone bottles. They are easy to fill, easy to clean, and can handle pressure changes without leaking.
- Label Everything: I use a label maker or a permanent marker. “Face Wash” and “Contact Solution” look very similar at 6 AM.
- Don’t Overfill: I only fill them 80% of the way. This leaves room for air pressure expansion and prevents leaks.
The “One-Quart Bag” Itself
My advice: throw away the flimsy sandwich bag. It will tear, the zip-lock will fail, and it’s a pain to pack.
I spent about $10 on a “TSA-compliant” reusable clear bag. It’s made of thick, durable vinyl and has a proper zipper. It’s structured, so it’s easier to pack, and I’ve had the same one for three years. It’s one of the best small investments I’ve made.
My Step-by-Step Security Checkpoint Process
Here’s how it all comes together. This is my exact, repeatable process that has passed security in over 15 countries without a single issue.
- While Packing: All my solid toiletries (shampoo bar, soap, toothpaste tablets, deodorant stick) are packed in my main toiletry bag inside my backpack. They are not liquids. They do not need to be separated.
- The Clear Bag: My only liquids (contact solution, face cream) go into my durable, 1-quart clear bag. This bag is now tiny and half-empty.
- Before Security: I place this small clear bag in the top “quick-access” pocket of my backpack. It’s the last thing I pack before zipping up.
- At the Bin: When I get to security, I pull out two things: my laptop and that one small, clear bag.
- The Result: I walk through. There is no scrambling, no re-packing, no stress. The agents see my tiny, compliant bag and wave me on.
What About “Medically Necessary” Liquids?
This is a critical exception. The 100ml rule does not apply to medically necessary liquids, baby formula, and breast milk.
- Examples: Prescription medications, insulin, eye drops, or contact lens solution (though I find it’s easier to just keep it in the 3-1-1 bag).
- My Advice: You must declare these to a security officer. I keep them separate from my 3-1-1 bag. As I approach the agent, I’ll hold the bag and say, “I have liquid prescription medication here to declare.”
- The Rule: You are allowed “reasonable amounts” over 100ml. Don’t try to bring a gallon. For all the official details, I recommend reading the official guidelines. The TSA’s page on the liquids rule is a great resource, even for international travel, as most countries have similar rules.
FAQs
1. Is toothpaste a liquid?
Yes. All pastes and gels (like toothpaste) fall under the 3-1-1 rule. That’s why toothpaste tablets are such a great solution.
2. Are solid shampoo bars really as good as liquid shampoo?
In my experience, yes—if you buy a good one. Avoid simple soap bars marketed as shampoo. Look for pH-balanced, surfactant-based bars. They clean just as well, and I find my hair feels healthier.
3. Can I bring a disposable razor or an electric razor?
Yes. Disposable razors and their cartridges are perfectly fine in a carry-on. Electric razors are also allowed.
4. Does my 1-quart bag have to be a specific brand or type?
No. It just needs to be clear, re-sealable, and roughly one quart (or one liter) in size. A simple Ziploc bag works, but I highly recommend upgrading to a more durable, zippered vinyl bag.
My Final Thought: It’s About Freedom, Not Just Rules
The 3-1-1 rule isn’t a challenge to be beaten; it’s a system to be navigated. For me, minimalist travel has always been about one thing: freedom.
Freedom from checked bag fees, freedom from lost luggage, and freedom from being weighed down. By switching to solid toiletries, I found a new freedom: freedom from security stress. I no longer worry about leaks, spills, or having an agent confiscate my things.
The entire process is simple, repeatable, and calm. If you’re new to this, don’t try to replace everything at once. Start with one swap. Try a shampoo bar on your next trip. See how it feels. That’s how my own journey started, and it has made all the difference.
