Can You Bring a Pocket Knife on a Plane? Assume No Until the Page Names an Exception

You cannot bring a pocket knife on a plane in a U.S. carry-on bag. The Transportation Security Administration's Knives page, last updated September 14, 2023, lists knives as No in carry-on bags and Yes in checked bags, except knives with rounded blades and blunt edges without serration, such as butter knives, or plastic cutlery. That page names no blade-length exception. If a published screening rule does not name an exception, the safest assumption is that there is none. Sheathe the knife, put it in a checked bag before the airline's bag-drop deadline, or leave it at home.

I spent eleven years driving sealed doping-control samples from venues to the laboratory and logging a temperature at every stop. My father drove a similar route for a blood bank and treated a cooler as a document. A detection window quoted without the laboratory's published method is a number with no meaning. A pocket-knife rumor quoted without the live item page is the same kind of number. TSA pocket knife rules and the TSA sharp objects list both end with the same line: the final decision rests with the TSA officer.

Does TSA allow a pocket knife in a U.S. carry-on, or only in checked baggage?

For a TSA-screened departure, a pocket knife belongs in checked baggage. The complete list's Pocket Knife row says you are prohibited from traveling with sharp objects in carry-on baggage and should pack those items in checked baggage. Swiss Army Knife is Carry On: No, Checked: Yes, with the same butter-knife exception.

Carry-on and checked are different documents, the way a collection form and a laboratory accession sheet are different documents. Every TSA sharp-object page I opened for this article repeats the packing sentence: any sharp objects in checked bags should be sheathed or securely wrapped to prevent injury to baggage handlers and inspectors. The Knives page publishes no maximum blade length for the hold.

Does blade length, folding design, or the number of blades create a carry-on exception?

No. TSA's Knives page lists no carry-on blade-length figure. Folding design is not listed as an exception. Number of blades is not listed as an exception.

In March 2013 TSA announced a plan to allow some non-locking folding knives with blades 2.36 inches (6 centimeters) or shorter and less than 1/2 inch wide. Politico reported on June 5, 2013, that TSA dropped that plan the same day. The live Knives page, updated September 14, 2023, still carries no 2.36-inch line.

Leatherman's Wave Plus spec sheet lists a primary blade length of 2.92 inches. At 2.54 centimeters per inch, that blade is 7.42 centimeters, longer than the unused 2.36-inch proposal. Closed length on the same sheet is 4 inches. Closed length is not blade length.

TSA's Multi-tools page, last updated April 17, 2018, decides the bag on a different field: "Multi-tools (multipurpose tools) with knives of any length are prohibited." One knife blade is enough. Zero knife blades is the only configuration that page treats as a possible carry-on. TSA's Scissors page, last updated May 11, 2017, allows scissors in carry-on bags if they are less than 4 inches from the pivot point (10.16 centimeters). That measurement is for scissors, from the fulcrum.

How does a Leatherman-style multitool compare with a pocket knife at the checkpoint?

TSA's Multi-tools page allows a multitool in carry-on bags only under special instructions: no knife of any length, and scissors less than 4 inches if scissors are the sharp implement. The Wave Plus fails that test on Leatherman's own tool list: 18 tools, including a 420HC knife (tool 07) and a 420HC serrated knife (tool 08), plus a saw and spring-action scissors. Closed length 4 inches, weight 8.5 ounces (240.97 grams).

Leatherman's Knifeless Rebar lists 16 tools and uses scissors instead of a knife blade, yet still lists a saw as tool 07. TSA's Multi-tools page names knives, not saws. If the page does not say a saw on a multitool may enter the cabin, I pack the tool in checked baggage.

| Tool | Knife blades on the spec sheet | TSA carry-on | TSA checked | Figure the page actually uses | | --- | --- | --- | --- | --- | | Folding pocket knife | 1 or more | No | Yes, sheathed or wrapped | No blade-length figure on Knives (updated Sept. 14, 2023) | | Leatherman Wave Plus | 2 (420HC knife and 420HC serrated knife) among 18 tools; primary blade 2.92 in | No (knife of any length) | Yes, sheathed or wrapped | Knife presence, Multi-tools page (updated April 17, 2018) | | Standalone scissors | 0 | Yes if less than 4 in from the pivot | Yes, sheathed or wrapped | 4 in from pivot, Scissors page (updated May 11, 2017) | | Knifeless Rebar | 0 knife blades; scissors plus a saw among 16 tools | Unstated for the saw; officer decides | Yes, sheathed or wrapped | Knives of any length are prohibited; saw is not named as allowed |

Fly with a Leatherman only after you have read the tool list. If any line on the spec sheet says knife, the TSA Multi-tools page has already classified the object.

What happens if TSA finds a pocket knife in a carry-on at the checkpoint?

A pocket knife confiscated by TSA does not continue through the X-ray as a cabin item. TSA's June 20, 2025 Charlotte Douglas release, on a knife and saw hidden in a walking cane, recorded four options the officer gave that traveler: return the item to a car, leave it with a non-traveling companion, place it in checked baggage, or voluntarily abandon it. TSA's civil-enforcement FAQ states that federal law and operational considerations restrict the return of prohibited items left at the checkpoint.

TSA may impose civil penalties of up to $17,062 per violation per person. For switchblades, gravity knives, daggers, cleavers, sabers, swords, and machetes, the sanctions table lists a warning on a first violation, then $450 to $2,570. A common slipjoint pocket knife is still prohibited in the cabin.

On October 14, 2022, TSA's BWI release listed Leathermans among knives found at checkpoints.

How should a pocket knife be sheathed for checked baggage, and when must the bag be at the counter?

TSA's packing rule is one sentence: sheathed or securely wrapped. The agency does not publish sheath dimensions. When a required field is blank, I do not invent a TSA number. Leatherman's nylon sheath product page lists a Medium size for the Wave Plus: overall length 4.84 inches, width 1.81 inches, depth 0.88 inches, at 1 ounce.

TSA does not set checked-bag weight allowance. United Airlines' checked-bags page sets United Economy and Premium Economy at 50 pounds (23 kilograms) per bag. American Airlines' checked-bag policy, updated as of May 18, 2026, uses the same 50 lbs / 23 kgs figure.

The bag-check deadline is an airline clock. United's airport-process page requires check-in at least 45 minutes before departure with checked bags, and at least 60 minutes on international flights (30 minutes with no checked bags). American Airlines' flying-with-American page uses the same 45-minute / 60-minute pair for most cities. After those times, traveling with a knife means the tool stays at the airport.

What changes if the itinerary connects in another country, such as the United Kingdom?

A U.S. departure answer does not travel with the boarding pass. If bags are through-checked, the knife stays in the hold. If you reclear security, or collect and re-check bags, the connection country's hand-luggage list applies.

The United Kingdom is the connection I would open first on a U.S.-to-Europe ticket that stops in London. GOV.UK's hand-luggage guide lists "Knife (with a sharp or pointed blade and/or blade longer than 6cm)" as No in hand luggage and Yes in hold luggage, with a note to check with the airline. Six centimeters is 2.36 inches, the same length TSA proposed and then dropped in 2013. A Wave Plus primary blade of 2.92 inches (7.42 centimeters) exceeds that 6-centimeter line even before the "sharp or pointed" clause is applied.

London City Airport's security-and-baggage table lists Multi-tools as No in hand baggage and Swiss Army knives with a tool or corkscrew as No in hand baggage.

Read the departure-country rule date and the connection-country list as two logs, the way I logged temperature at the venue and again at the laboratory door. TSA Knives: last updated September 14, 2023. TSA Multi-tools: last updated April 17, 2018. TSA Scissors: last updated May 11, 2017. When those dates disagree, I follow the Knives page for anything that is a knife.

What should you do when a published detail is missing?

Assume the stricter reading, then pack for that reading. I used that method when a courier sheet omitted a storage temperature: the sample still had to arrive inside the laboratory's published range.

1. Open the departure-country item page (for a U.S. airport, TSA Knives) and write down the last-updated date.
2. Open the manufacturer's spec sheet and count knife blades, including serrated blades. For a Wave Plus, the count is 2.
3. If the count is 1 or more, sheathe or wrap the tool. Leatherman's medium nylon sheath for the Wave Plus is 4.84 by 1.81 by 0.88 inches.
4. Place the sheathed tool in a checked bag that meets the airline weight limit (United Economy: 50 pounds / 23 kilograms) and the bag-drop deadline (United, with bags: 45 minutes domestic, 60 minutes international).
5. If any connection reclears cabin bags, open that country's hand-luggage list. For the United Kingdom, GOV.UK's 6-centimeter knife line is the number to compare with your blade.
6. If you cannot check a bag, leave the knife at home or ship it.

AskTSA answers unlisted items live from 8 a.m. to 6 p.m. Eastern Time, 365 days a year (text Travel to 275-872). A chat log is not a substitute for the Knives page dated September 14, 2023. If the officer and the page disagree, the officer at that checkpoint is the method in force.

FAQ

Can you bring a pocket knife on a plane in your carry-on?

No. TSA's Knives page, last updated September 14, 2023, lists knives as No in carry-on bags and Yes in checked bags, except rounded-blade butter knives and plastic cutlery. It names no blade-length exception. The TSA officer at the checkpoint makes the final decision on whether the item goes through.

Does TSA allow folding knives under 2.36 inches in carry-on?

No. A March 2013 TSA plan would have allowed some non-locking folding blades 2.36 inches (6 centimeters) or shorter. Politico reported on June 5, 2013, that TSA dropped the plan. The live Knives page still lists no length exception. A Leatherman Wave Plus primary blade is 2.92 inches.

Can I fly with a Leatherman in my carry-on bag?

Only if the tool has no knife blade of any length. TSA's Multi-tools page, updated April 17, 2018, prohibits multitools with knives of any length in carry-on bags. Leatherman's Wave Plus lists two knife implements among 18 tools, with a 2.92-inch primary blade. Pack that model sheathed in checked baggage.

What happens if TSA finds a pocket knife in my bag?

The officer will stop it. TSA's June 20, 2025 Charlotte release listed four options used there: return the item to a car, leave it with a companion, place it in checked baggage, or abandon it. TSA says prohibited items left at the checkpoint are generally not returned. Checking the bag only works if you still meet the airline's bag-drop time.

How should I pack a pocket knife in checked baggage?

TSA requires sharp objects in checked bags to be sheathed or securely wrapped. It publishes no sheath dimensions. Leatherman's medium nylon sheath, listed for the Wave Plus, measures 4.84 by 1.81 by 0.88 inches. Get the bag to the counter before the airline deadline; United requires 45 minutes with bags on most domestic flights.

Can I take a pocket knife through UK airport security on a connection?

GOV.UK bans in hand luggage a knife with a sharp or pointed blade and/or a blade longer than 6 centimeters. A Wave Plus primary blade of 2.92 inches is 7.42 centimeters. London City Airport lists multi-tools as No in hand baggage. Keep the tool in through-checked hold luggage if the itinerary reclears cabin bags in the United Kingdom.