Can you take a laptop on a plane? Rules by country

Q: Can you take a laptop on a plane?

On flights in and from Japan: Yes. A laptop with a lithium-ion battery of 160Wh or less can be carried on. Take it out of your bag and put it in a separate tray at screening. In checked baggage: Allowed if the battery is 160Wh or less, the laptop is switched completely off and it is protected from damage.

Q: Do you have to take your laptop out of your bag at security in Japan?

Yes. Narita Airport asks passengers to remove personal computers and other large electronic devices from carry-on baggage and place them in a separate tray, and calls this the policy of the transport ministry. The European Commission's guidance for EU airports reads the same way. In the United States the TSA lets PreCheck travellers leave laptops in the bag.

Q: Can a laptop go in a checked bag in sleep mode?

No. Hong Kong's CAD and Australia's CASA both say a device in checked baggage must be completely switched off, not in sleep or hibernation mode, and Taiwan's CAA uses the same words. Japan's list requires the power to be completely off and the laptop protected against damage, and gives a sturdy suitcase and padding with clothes as examples.

Q: Can you take a laptop in hand luggage in the UK or Europe?

The United Kingdom: Laptops are allowed in hand luggage and hold luggage. Make sure yours is charged: if a device does not switch on when requested, you will not be allowed to take it onto the aircraft. The European Union: Carry laptops in hand baggage, not checked baggage. If one must go in checked baggage (not recommended), it has to be completely switched off and protected from accidental activation. At security, put it in a tray for separate screening.

Q: What is the rule for laptops on flights from Mainland China, Australia and South Korea?

Mainland China: Lithium battery in a portable device: up to 100Wh can be carried on; over 100Wh and up to 160Wh needs airline approval. Checked: lithium batteries are banned and digital electronics should not be packed; ask the airline about such devices. Australia: Carry-on or checked; carry-on is recommended. Lithium ion batteries must not exceed 100 Wh; above 100Wh up to 160Wh needs airline approval. If checked, the laptop must be completely switched off (not in sleep or hibernation mode). South Korea: Laptops are named among devices with a lithium battery installed: allowed in carry-on and checked baggage at 100Wh or less (lithium-ion); over 100Wh up to 160Wh needs airline approval. At screening, laptops go on the X-ray belt.

Laptops on flights in and from Japan

The rule for laptops comes from the Civil Aviation Bureau's list of restricted items and is the same on domestic and international flights.

Laptops: carry-on and checked baggage in Japan
Where	Allowed?	What applies
In the cabin	Yes	Yes. A laptop with a lithium-ion battery of 160Wh or less can be carried on. Take it out of your bag and put it in a separate tray at screening.
In checked baggage	Conditions	Allowed if the battery is 160Wh or less, the laptop is switched completely off and it is protected from damage.

Narita AirportNarita says, as MLIT policy, to take personal computers and other large electronic devices out of your carry-on bag and put them in a separate tray at security screening.Narita International Airport FAQ

Laptops at screening, in sleep mode and with spare batteries

A laptop gets its own tray at Narita, and in a checked bag the question is whether it is really off.

The separate tray is for every large device: Narita's request for a separate tray is not limited to laptops. Its FAQ says large stationary game consoles go in a tray of their own too, and mentions no such step for portable consoles. The TSA words its desktop computer and full-size console entries the same way. At Hong Kong International Airport the smart lanes use CT-based X-ray scanners, and electronic devices may stay in hand baggage.
Over 100Wh: no extra step in Japan, airline approval elsewhere: Japan's list treats a laptop battery of any size up to 160Wh the same way. Australia's CASA, Hong Kong's CAD, Taiwan's CAA and South Korea's list draw a line at 100Wh: above it, up to 160Wh, the airline has to agree first. CASA also recommends taking a device of that size into the cabin.
Extended-life and second batteries: A second battery for a laptop is a spare and rides in the cabin. The TSA notes that its 101 to 160 Wh class covers the larger after-market extended-life laptop batteries: these need airline approval and are limited to 2 per person. Japan's leaflet also allows up to 2 spares over 100Wh up to 160Wh, but power banks of that size count toward the same 2.
Notebooks, parts and external drives: CASA's Laptop entry says it includes personal computers and other similar electronic devices, and the same category lists Notebook, Netbook and PC. The TSA keeps a separate entry for disassembled computers, computer parts and external hard drives: yes for carry-on and yes for checked bags, with nothing further written under it.

Laptops: the rule country by country

Extra conditions apply in Mainland China and Australia.

Laptops: carry-on and checked baggage rules by country
Flying from	Carry-on	Checked bag	What the authority says
JapanCivil Aviation Bureau	Yes	With limits	A laptop with a lithium-ion battery of 160Wh or less can be carried on. Take it out of your bag and put it in a separate tray at screening. Source
United StatesTSA	Yes	Yes	Laptops are allowed in carry-on and checked bags. Remove the laptop from your bag and place it in a separate bin for X-ray screening; TSA PreCheck travelers do not need to remove laptops.TSA entry: Laptops Source
European UnionEuropean Commission, EASA	Yes	With limits	Carry laptops in hand baggage, not checked baggage. If one must go in checked baggage (not recommended), it has to be completely switched off and protected from accidental activation. At security, put it in a tray for separate screening. Source
United KingdomUK Government	Yes	Yes	Laptops are allowed in hand luggage and hold luggage. Make sure yours is charged: if a device does not switch on when requested, you will not be allowed to take it onto the aircraft. Source
South KoreaMOLIT Aviation Security 365	Yes	Yes	Laptops are named among devices with a lithium battery installed: allowed in carry-on and checked baggage at 100Wh or less (lithium-ion); over 100Wh up to 160Wh needs airline approval. At screening, laptops go on the X-ray belt. Source
TaiwanCivil Aviation Administration	Yes	With limits	A portable electronic device with a lithium battery: carrying it in hand baggage is recommended. If checked with a lithium-ion battery over 2.7 Wh, it must be completely switched off (not in sleep or hibernation mode). Source
Hong KongCivil Aviation Department	Yes	With limits	Laptops are named as portable electronic devices allowed in carry-on and checked baggage. In checked baggage they must be completely switched off (not in sleep or hibernation mode) and protected from damage and unintentional activation. Source
Mainland ChinaCAAC	With limits	With limits	Lithium battery in a portable device: up to 100Wh can be carried on; over 100Wh and up to 160Wh needs airline approval. Checked: lithium batteries are banned and digital electronics should not be packed; ask the airline about such devices. Source
AustraliaHome Affairs, CASA	With limits	With limits	Carry-on or checked; carry-on is recommended. Lithium ion batteries must not exceed 100 Wh; above 100Wh up to 160Wh needs airline approval. If checked, the laptop must be completely switched off (not in sleep or hibernation mode).CASA Pack Right entry: Laptop, Portable electronic devices containing lithium metal or lithium ion cells, battery or batteries (watches, calculators, cameras, mobile phones, laptops, camcorders etc.), Portable electronic devices containing lithium ion batteries (batteries >100 Wh and <160 Wh) Source

Each row comes from that authority's own page. Airlines can be stricter, and the screening officer has the final say.

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