The short answer is that most knives are not allowed to be carried on the plane by passengers.
Based on TSA Guidelines, travelers are allowed to bring chef and pocket knives in their checked luggage, but they are not allowed in the carry-on luggage.
If you want to bring knives onto a plane, usually it would have to be in your checked luggage.
The exception is that plastic knives and round-bladed butter knives are usually allowed to be carried in your carry-on luggage, but these laws are constantly changing, so be sure to double check with the airport or the TSA before bringing any kind of knife into an airport.
There was a brief repeal in 2013 which temporarily allowed pocket knives to be carried in carry-on luggage but this repeal met extreme push-back and pocket knives are yet again no longer allowed in carry-on luggage.
(Related article: Why Do Chef Knives Have Dimples?)
Other Prohibited Items
Keep in mind that knives are not the only items which are regulated during plane travel.
Some other items include the following:
- Firearms and ammunition.
- Box cutters and similarly sharp objects.