Can you take a travel mug on a plane?

Yes, you can take a travel mug on a plane. Carry it through security empty, fill it at an airport café or on board, and drink your coffee at 35,000 feet from a cup you actually like.

The coffee is the liquid. The mug is just a mug. Here's how to keep your morning ritual intact from check-in to touchdown.

Travel mug airport security rules: Australia, UK and US

An empty travel mug or reusable coffee cup is fine in your carry-on, whether it's insulated steel, glass or plastic. A mug with coffee in it follows the same liquid rules as any other drink.

Even where a full mug is allowed, finishing your flat white before the queue is quicker. Officers may need to check liquids in opaque or insulated steel containers, and a half-drunk latte in the tray slows everyone down.

Rules are changing as airports install CT scanners, so check your airport before you fly. Empty works everywhere.

Getting coffee in your own cup at the airport

Hand your travel mug to the barista when you order. Most airport cafés will make your coffee straight into it. Size up to match: a small cup suits a flat white or filter, a medium fits a latte or cappuccino.

On board, cabin crew can fill your mug with tea, coffee or hot water during drinks service. Ask when the trolley comes past. It's one less paper cup, and your drink stays hot through the movie instead of going cold by the opening credits.

In the lounge? Same deal. The coffee machine doesn't mind what cup you bring.

Hot drinks on a plane: pressure, steam and lids

Cabin pressure drops at cruising altitude, and a sealed mug of hot coffee holds steam that wants to expand. Open a tight lid too fast and you'll wear some of it.

Crack the lid slowly and point the drinking hole away from you. A leakproof lid with a sliding or flip closure lets you release pressure gently. If your mug is half full, keep it upright in the seat pocket and close it fully during turbulence. Your tray-table neighbour will thank you.

The best travel mug for flying

The best travel mug for a plane is insulated, leakproof and goes in your bag without a second thought. The KeepCup Commuter is a vacuum-insulated stainless steel travel mug with a leakproof lid, voted Best Travel Mug by The Guardian. Coffee stays hot from the gate to the baggage carousel, and nothing escapes into your carry-on.

Prefer to taste coffee as the barista made it? The KeepCup Brew Cork is tempered soda lime glass with a cork band. It's at home in a café queue and fine through security empty. For a long-haul bag, the Commuter is the safer bet.

KeepCup was founded in Melbourne in 2009 by Abigail and Jamie Forsyth, the first barista-standard reusable coffee cup. We're a certified B Corp and the only reusables company to back our claims with a peer-reviewed Life Cycle Assessment. The best reusable is the one you use, including at the airport.

Shop the Commuter Travel Mug >

Travel mugs on planes: FAQ

Can I bring an empty coffee cup through airport security? Yes. Empty travel mugs and reusable coffee cups are allowed in carry-on bags in Australia, the UK and the US.

Can I take coffee through security in Australia? On domestic flights, yes. On international flights, finish it first: the 100ml limit applies.

Will flight attendants fill my travel mug? Usually, yes. Ask during drinks service for coffee, tea or hot water.

Can I take a glass coffee cup on a plane? Yes. Glass is allowed in carry-on. Tempered glass handles travel well, and a padded side pocket helps.

Does a travel mug count towards my carry-on allowance? It sits in your bag like any other item. Check your airline's weight limit if you're travelling light.