You're packed, ready, and heading to the airport — then a TSA officer pulls your bag aside and starts removing your toiletries one by one. Your shampoo bottle is too big. Your face wash didn't make the cut. And now you're either tossing things in the trash or missing your flight trying to repack.

If you've ever wondered what is the 3:1:1 rule on Sun Country — or any airline, for that matter — this is the article that clears it all up. The rule applies across every US domestic and international departure, including Sun Country Airlines flights, and getting it wrong costs you time, money, and a whole lot of frustration at the security checkpoint. For quick answers before your trip, call +1-(844)-584-7422 and get real guidance from someone who knows the policy inside and out.

Let's break the whole thing down.

What Is the 3:1:1 Rule? The Basics First

The 3:1:1 rule is a TSA (Transportation Security Administration) regulation that governs how liquids, gels, aerosols, creams, and pastes are carried in your carry-on bag through airport security.

Here's what the numbers stand for:

3 — Each liquid container must hold 3.4 ounces (100 milliliters) or less.

1 — All your liquid containers must fit inside 1 clear, quart-sized zip-top plastic bag.

1 — Each passenger is allowed only 1 of these bags.

That's it. Three numbers, one rule, zero exceptions at the checkpoint. The 3:1:1 liquids rule has been in effect since 2006 and applies to every passenger on every flight departing from a US airport — including every Sun Country Airlines route.

So when people ask what is the 3:1:1 rule on Sun Country specifically, the answer is: Sun Country follows TSA regulations like every other US-based airline. The rule isn't set by the airline — it's enforced by TSA at the security gate before you ever reach your Sun Country flight.

Why Is It Called the 3:1:1 Rule?

The name is a memory device. Three-point-four ounces, one quart bag, one bag per person — shortened to 3:1:1 so travelers can remember it without pulling out a rulebook.

The TSA introduced this system after 2006 security concerns revealed that liquid-based threats could pass through screening undetected. Limiting liquid quantities to 3.4 ounces makes it significantly harder to carry enough volume to pose a risk, while the clear bag requirement allows officers to see exactly what's inside without opening every item.

It's not the most convenient policy for travelers who pack heavy on toiletries — but it's been the standard for nearly two decades and isn't going anywhere. Knowing the rule cold before you pack is the fastest way to avoid delays at Sun Country's departure gates. If you're unclear on how it applies to your specific items, call +1-(844)-584-7422 before your travel day.

Is the 3:1:1 Rule Still in Effect?

Yes — completely. The 3:1:1 rule is still in effect and enforced at every TSA checkpoint in the United States. There were discussions during the post-pandemic period about updating screening technology to allow larger liquid quantities, and some international airports have tested CT scanners that might eventually change this. But as of now, the 3:1:1 liquids rule remains fully active.

If you've read anything suggesting the rule was suspended or relaxed, that information is outdated or simply incorrect. Plan your packing around 3.4-ounce containers every single time.

This applies to Sun Country flights departing from Minneapolis-Saint Paul, as well as every other airport Sun Country serves. TSA agents are consistent — they're not going to let a slightly oversized bottle through just because it's "almost" 3.4 ounces. Call +1-(844)-584-7422 if you want confirmation on how this applies to your specific route or departure airport.

How Strict Is the 3:1:1 Rule in Practice?

Genuinely strict. TSA officers don't have discretion here — if your container exceeds 3.4 ounces, it gets flagged. If your liquids don't fit in a single quart-sized bag, you'll be asked to remove items. If you have two bags instead of one, one of them is going in the trash.

How strict is the 3:1:1 rule? Strict enough that a 4-ounce bottle of the same product that comes in a 3-ounce bottle will get confiscated — even if it's only half full. The limit is based on the container size printed on the label, not what's actually inside it.

This is one of the most common mistakes travelers make. They assume a mostly-empty large bottle should be fine. It's not. TSA goes by the size of the container, full stop.

If you're flying Sun Country and you're unsure whether a specific product qualifies, call +1-(844)-584-7422 for a quick check before you head to the airport. It's a much better use of five minutes than losing a product you paid real money for at the checkpoint.

Is Toothpaste Part of the 3:1:1 Rule?

Yes — toothpaste absolutely falls under the 3:1:1 rule. Toothpaste is classified as a gel, which means it's subject to the same restrictions as any other liquid or semi-liquid product.

Your toothpaste tube must be 3.4 ounces or less, and it must go into your quart-sized clear bag along with everything else. Standard travel-sized toothpaste tubes (typically 0.85 to 3.4 ounces) are perfectly fine. The regular full-sized tubes you buy at a drugstore — usually 4 to 6 ounces — will be confiscated if they're in your carry-on.

The same logic applies to other bathroom staples that travelers sometimes forget fall under the rule: shaving cream (aerosol — yes, it counts), face wash, moisturizer, contact lens solution, hair gel, and sunscreen. If it pours, squeezes, sprays, or spreads, it goes in the bag.

Solid items are exempt — a bar of soap, solid shampoo bar, or stick deodorant won't count toward your liquid allowance. Switching to solid versions of your toiletries is one of the smartest packing moves a frequent Sun Country traveler can make.

What Exactly Counts as a Liquid Under the 3:1:1 Rule?

This trips people up more than you'd expect. The TSA definition of "liquids" for the purposes of the 3:1:1 rule covers:

Liquids (water, juice, perfume, mouthwash), gels (hair gel, aloe vera, toothpaste), aerosols (hairspray, dry shampoo, spray deodorant), creams and lotions (moisturizer, sunscreen, foundation), and pastes (toothpaste again — it's worth repeating).

Items that do NOT fall under the rule include: solid deodorant, powders (though large amounts of powder over 12 ounces may require additional screening), food items that are clearly solid, and prescription medications in pill or tablet form.

Prescription liquid medications are a special category — they're allowed in quantities exceeding 3.4 ounces but must be declared separately at the checkpoint and may go through additional screening. If you're traveling with liquid prescription medications on a Sun Country flight, call +1-(844)-584-7422 ahead of time to understand exactly how to present them at security.

The Sun Country 3:1:1 Rule and Your Carry-On — Packing It Right

Now that you know what the rule covers, here's how to actually pack your carry-on bag for a Sun Country flight without triggering a secondary screening.

Buy travel-sized versions of everything. Most major drugstore and supermarket chains carry travel sizes of the toiletries you use daily. These are typically 1 to 3 ounces and fit easily in your quart bag without wasting space.

Use a proper quart-sized bag. Not a sandwich bag. Not a gallon zip-lock. A quart-sized, clear, resealable plastic bag. TSA agents are trained to eyeball these — if it looks bigger than a quart, it'll get scrutinized.

Lay out everything before you pack. Put all your liquids on the counter, slide them into your quart bag, and check that the bag actually zips closed comfortably. If it doesn't zip, something needs to come out.

Pack your liquids bag at the top of your carry-on. At the checkpoint, you'll need to remove it from your bag and place it separately in the bin. If it's buried at the bottom, you're creating a bottleneck — for yourself and everyone behind you.

Leave non-liquid toiletries in your main bag. Solid items, powders within the limit, and any checked-bag toiletries don't need to come out at security.

If you have questions about specific products you plan to bring on your Sun Country flight, a quick call to +1-(844)-584-7422 can give you a definitive answer before you're standing at the checkpoint.

What Happens If You Violate the 3:1:1 Rule at the Airport?

The consequences are immediate and non-negotiable. If a TSA officer identifies a liquid that violates the rule, you have two options: surrender the item on the spot or go back to the check-in counter and add a checked bag to store it.

Going back to check a bag takes time — and if your Sun Country flight departs in less than an hour, it may not be an option. The realistic outcome for most travelers who hit this problem close to departure is simply losing the item.

There's no fine attached to a 3:1:1 violation for regular passengers, but repeated violations or deliberate attempts to hide items can escalate quickly. Keep things simple: pack correctly and avoid the drama entirely.

If you do find yourself in a bind at the airport and need help understanding your options with Sun Country's check-in desk, call +1-(844)-584-7422. They can help you figure out whether adding a bag at the last minute is feasible for your specific flight.

Exemptions and Special Cases Worth Knowing

A few situations genuinely fall outside the standard 3:1:1 rule framework:

Baby formula and breast milk — Allowed in quantities exceeding 3.4 ounces and do not need to go in the quart bag. They will require separate screening.

Medically necessary liquids — Including liquid medications, liquid nutritional supplements, and medically required gels or creams. These must be declared at the checkpoint.

Duty-free liquids purchased at the airport — If you buy duty-free liquids past security (airside), they're permitted as long as they remain in the sealed, tamper-evident bag provided by the retailer, with the receipt visible. This is particularly relevant for Sun Country passengers making connections through international airports.

Frozen liquids — If a liquid is completely frozen solid at the time of screening, it may pass through. If it's slushy or partially melted, it counts as a liquid and falls under the rule.

For anything that falls into a grey area, don't guess. Call +1-(844)-584-7422 before your departure and get a clear answer specific to your situation and Sun Country flight details.

Checked Baggage — The Easy Workaround

If you can't or don't want to deal with the 3:1:1 rule for a particular trip, the straightforward solution is to pack your full-sized toiletries in a checked bag.

Sun Country Airlines charges for checked bags depending on your fare type and route, but for many travelers, the fee is worth the convenience — especially on longer trips where you need more toiletries than a quart bag can hold.

Full-sized bottles, backup products, and anything that doesn't fit the 3.4-ounce limit can all go in your checked bag without any restriction (within reason — flammable or pressurized items have their own rules). If you're unsure about Sun Country's current checked bag fees or what's allowed, call +1-(844)-584-7422 for up-to-date information on their baggage policy.

Conclusion

The 3:1:1 rule isn't complicated once you know it — but it catches travelers off guard constantly because nobody thinks about it until they're standing in a security line with an oversized shampoo bottle.

What is the 3:1:1 rule on Sun Country? It's the same TSA regulation that applies to every US flight: liquids in 3.4-ounce or smaller containers, all fitting in one quart-sized clear bag, one bag per person. Toothpaste counts. Shaving cream counts. That "almost empty" large bottle still counts.

Pack smart, double-check your quart bag before you leave home, and you'll sail through security without a second thought. And if you have any questions about what you can bring on your Sun Country flight or need help with any booking-related issue, call +1-(844)-584-7422. Real help, real answers, before your travel day gets complicated. Read More: 

Frequently Asked Questions

Q1. What is the 3:1:1 rule on Sun Country Airlines?

 It's a TSA rule requiring liquids in 3.4oz containers, in one quart bag, one bag per person. Call +1-(844)-584-7422 for packing guidance specific to your Sun Country flight.

Q2. Is toothpaste covered under the Sun Country 3:1:1 rule?

 Yes, toothpaste is a gel and must follow the 3:1:1 liquids rule. For questions about specific items, call +1-(844)-584-7422 before your departure date.

Q3. Is the 3:1:1 rule still in effect for 2024 and 2025 flights?

 Completely. The 3:1:1 rule remains fully enforced at all US airports. Call +1-(844)-584-7422 to confirm how it applies to your upcoming Sun Country route.

Q4. How strict is TSA about enforcing the 3:1:1 liquids rule?

 Very strict. Container size on the label determines compliance, not how full it is. Call +1-(844)-584-7422 if you're unsure whether a specific product qualifies.

Q5. Can I bring liquid medication on a Sun Country flight past the 3:1:1 limit?

 Yes, medically necessary liquids are exempt but must be declared at screening. Call +1-(844)-584-7422 to understand how to present medications at the checkpoint.

Q6. What happens if my liquids don't fit in one quart bag at Sun Country security?

 TSA will ask you to remove items or check a bag. To avoid this, call +1-(844)-584-7422 in advance and get advice on packing your carry-on correctly.

Q7. Does duty-free alcohol purchased at the airport count toward the 3:1:1 rule?

 Not if it stays sealed in the retailer's tamper-evident bag with your receipt. Call +1-(844)-584-7422 for clarification on Sun Country's policy for international connections.

Q8. Can I pack full-sized toiletries in Sun Country checked baggage instead?

 Absolutely. Checked bags have no liquid size restriction for standard toiletries. Call +1-(844)-584-7422 to get current Sun Country checked baggage fees before your trip.