🥤 Can you bring Vacuum flask / tumbler on a plane?

Cabin and checked, as long as it is empty

As of 2026-08-21

The rule in detail

The flask or tumbler itself is unrestricted and may go in the cabin or in checked baggage. What is restricted is the liquid inside: with water in it, the 100ml rule applies and security will ask you to empty it. A stainless vacuum wall is opaque to X-ray, so hand inspection is common — arriving with it empty and the lid easy to open is simply faster. Refill it at a water fountain once you are through.

Why the rule is written this way

It is classified as Carry-on or checked because it counts as an ordinary travel item, so there is no restriction on where it goes.

Either bag is fine. If its shape is the kind that invites a question at the checkpoint, keep it in an outer pocket of your cabin bag so you can produce it quickly.

What actually happens at the airport

  1. Check-in desk — this is the point of no return for your suitcase. Anything that may only travel in the cabin cannot be retrieved after this step.
  2. Security screening — if the X-ray flags a shape, the bag is opened. Most problem items are caught here.
  3. Extra check at the gate — on some routes there is one more inspection.

Confiscated items are rarely returned. If you are unsure, confirm the specification before you leave home.

💡 Worth knowing

A carbonated drink will force its way out as pressure drops — empty the flask completely before you check it

Other items in the same class

The items below are also classified as Carry-on or checked. Quantity and volume limits differ per item, so check each rule separately.

ItemRule
🔌 Corded hair straightener / hairdryerCabin: yes / checked: yes
✂️ Nail clippers / tweezers / eyebrow razorCabin: yes / checked: yes
💊 Medicine / prescriptions / supplementsCabin: yes / checked: yes (prescriptions on you)
📷 Tripod / selfie stickCabin: yes / checked: yes (length limits apply)

Frequently asked questions

Vacuum flask / tumbler — can I take it in the cabin?
Cabin and checked, as long as it is empty. The flask or tumbler itself is unrestricted and may go in the cabin or in checked baggage. What is restricted is the liquid inside: with water in it, the 100ml rule applies and security will ask you to empty it. A stainless vacuum wall is opaque to X-ray, so hand inspection is common — arriving with it empty and the lid easy to open is simply faster. Refill it at a water fountain once you are through.
Is there anything else to watch out for with Vacuum flask / tumbler?
A carbonated drink will force its way out as pressure drops — empty the flask completely before you check it

Worth checking at the same time

✅ See the packing lists by destination