The TSA 3-1-1 rule means: liquids must be in containers of 3.4 ounces (100 ml) or less each; all containers must fit inside one clear quart-sized zip-top bag; and each passenger is limited to one such bag. This applies to gels, creams, aerosols, and pastes too. Solid toiletries (bar soap, solid deodorant) are not restricted.

With smart packing techniques (rolling clothes, using packing cubes, and choosing versatile items), you can comfortably pack for 7–14 days in a standard carry‑on. For trips longer than two weeks, plan to do laundry once or twice. Many minimalist travelers travel indefinitely with just a carry‑on by washing clothes every 5–7 days.

The absolute must-haves: passport/ID, phone + charger, wallet/payment cards, any prescription medications, and travel insurance info. Everything else can usually be purchased at your destination if forgotten. Keep these critical items in your personal item (not just your carry‑on) in case your bag gets gate-checked.

Most airlines allow one carry‑on bag (fits in overhead bin, typically 22×14×9 inches) plus one personal item (fits under the seat, like a backpack, purse, or laptop bag). Budget airlines may charge extra for a full-size carry‑on but usually include a free personal item. Always check your specific airline's size and weight limits before packing.

Roll, don't fold – rolling clothes reduces wrinkles and saves space. Use packing cubes to compress and organize. Wear your bulkiest items (jacket, boots) on the plane. Choose versatile, neutral-colored clothing that mixes and matches. Use every hollow space – stuff socks inside shoes, fill corners with small items. A compression sack can shrink bulky layers significantly.

Most consumer electronics are allowed in carry‑ons: laptops, tablets, phones, cameras, e-readers, portable chargers (power banks under 100Wh), headphones, and small accessories. Power banks MUST go in carry‑on (not checked baggage). At security screening, laptops and larger tablets usually need to be removed from your bag and placed in a separate bin. Some airports now allow them to stay inside with newer CT scanners.

Backpacks are more versatile – easier on cobblestones, stairs, and public transit; they keep your hands free and often fit underseat. Wheeled suitcases are better for business trips, heavy loads, and smooth airport floors. Many travelers now prefer a high-quality travel backpack (35–45L) for maximum flexibility. Choose based on your destination's terrain and your physical comfort.

Prohibited items include: sharp objects (box cutters, large scissors, knives of any size), flammable liquids and gels over 3.4oz/100ml, firearms and ammunition, self-defense items (pepper spray, brass knuckles), tools longer than 7 inches, and sports equipment that could be used as a weapon (baseball bats, hockey sticks). When in doubt, check the TSA website or your local aviation authority.