Earthquake preparedness in Japan, 2026: before, during and after the shaking

Conclusion

Earthquake preparedness is easier to manage in three parts: before, during and after the shaking. The part that pays off most is what you do before. In the Cabinet Office's damage estimate for a Nankai Trough megaquake (published March 2025), retrofitting older buildings cuts deaths from collapsing buildings by about 77%, and wider use of seismic circuit breakers cuts deaths from fire by about 52%.

During the shaking, it is enough to remember one "protect yourself first" action for each kind of place. In the first hour afterwards, deal with fire, get away from any tsunami, then check on your family, in that order. Looking up what to do after a special advisory once it has been issued is too late, so the second half of this article covers that in advance.

Japan's earthquake risk in numbers

The government's Headquarters for Earthquake Research Promotion recalculates the probabilities of major earthquakes each year, using 1 January as the reference date. The latest figures were published on 14 January 2026, with a reference date of 1 January 2026. The Headquarters points out that strong shaking can hit anywhere in Japan, and urges people to reinforce buildings and secure furniture as a matter of routine.

The Nankai Trough has two figures because a partial revision of its long-term evaluation on 26 September 2025 began showing results from two calculation methods side by side. The previous "about 80%" falls within the range of the higher figure. The Headquarters says neither model can be judged scientifically better, and that when a specific figure is needed, the higher one should be stressed. In practice, the useful reading is that the Nankai Trough remains in the highest rank, rather than focusing on the gap between the numbers.

For the scale of damage, look at the Cabinet Office's estimates. A new estimate for the Nankai Trough was published on 31 March 2025, and one for a Tokyo-area inland quake on 19 December 2025.

• Nankai Trough megaquake (case with the heaviest damage in the Tokai region): about 65,000 to 298,000 deaths; about 966,000 to 2.34 million buildings destroyed or burned
• Tokyo inland earthquake (directly beneath southern central Tokyo): about 18,000 deaths; about 400,000 buildings destroyed or burned; about 4.8 million evacuees; about 8.4 million people unable to get home; 16,000–41,000 disaster-related deaths

The Nankai Trough estimate also shows how far countermeasures reduce the toll. Retrofitting older buildings brings deaths from collapse down from about 73,000 to 17,000 (about 77%), securing furniture from about 5,300 to 1,800 (about 66%, a reference value), and seismic breakers bring fire deaths down from about 21,000 to 10,000 (about 52%). The Tokyo report likewise lists housing retrofits, fixing furniture, seismic breakers and home stockpiles as what individuals and households should do.

For tsunamis, the Nankai Trough estimate finds that tsunami deaths differ by a factor of roughly 2.3 to 9.8 depending on whether many people start evacuating straight away. These figures assume the largest possible earthquake; they do not mean the next one will be that big. Even so, because they show how much each measure reduces the damage, they help a household decide what to do first.

Before the shaking: furniture, bedrooms, electricity and the building

Secure furniture and clear the bedroom

According to the Tokyo Fire Department's furniture safety handbook, about 30–50% of people injured in recent earthquakes were hurt by furniture falling over, dropping or sliding. Fallen furniture can also block doorways and slow your escape.

Start with bedrooms, children's rooms and the area around exits. When you are asleep, there is almost no time between noticing the shaking and protecting yourself. Place tall bookcases and wardrobes so they cannot fall onto a bed, and keep nothing above the head of the bed. Heavy appliances such as TVs and microwaves should be fixed on the assumption that they will fall.

Use a seismic breaker to prevent electrical fires after the quake

Figures compiled by a study group of the Cabinet Office, the Fire and Disaster Management Agency and the economy ministry show that 65% (71 of 110) of the fires with a known cause after the main shock of the 2011 Great East Japan Earthquake were electrical, as were 61% (85 of 139) after the 1995 Great Hanshin-Awaji Earthquake. These include fires from heaters that toppled over, and "power-restoration fires" that start from damaged wiring when electricity comes back.

A seismic circuit breaker cuts the power automatically when it detects shaking above a set level. There are types that cut the whole distribution board, types that cut a single socket, and simple add-ons that trip the breaker with a weight or spring. Because the house goes dark if this happens at night, pair it with a night light or torch. A Cabinet Office survey (September 2022) found only 5.2% of households had one (reference value). Some municipalities subsidise purchase or installation.

Check how earthquake-resistant your building is

The transport ministry estimates that about 90% of homes met earthquake resistance standards in 2023, leaving about 5.7 million homes that do not. For detached houses alone, the figure is about 85%. Homes built in 1981 or earlier deserve the closest look.

Many municipalities cover part of the cost of seismic assessments and retrofits. Eligibility and amounts vary, so check with your city or town office or its website. If you rent, a good first step is to ask the management company when the building was built and whether it has been assessed.

Our column "How many days of supplies at home and at work? Rolling stock and people with special needs" covers stockpiling water and food.

During the shaking: what to do where you are

The Japan Meteorological Agency (JMA) notes that there are only a few seconds to a few tens of seconds between an earthquake early warning and strong shaking, and advises staying calm and protecting yourself first, according to your surroundings. The table below summarises the JMA's guidance by location.

Near the sea, the rule is the reverse of "wait until it stops": leave as soon as the shaking eases. The JMA stresses that if you wait until you see a tsunami reaching the shore it is too late, and that you should evacuate whenever you see or hear a tsunami warning, even if you felt no shaking. On beaches, a red-and-white chequered tsunami flag is also a signal to evacuate.

Our article on earthquake early warning drills explains how to check that your phone will receive real warnings.

The first hour after the shaking

Having a fixed order for the hour after the shaking stops reduces hesitation.

1. Check yourself and your surroundings: look for injuries, and put on shoes or slippers to protect your feet from broken glass
2. Deal with fire: if you were cooking, turn it off once the shaking stops. Unplug electric heaters
3. If you are in a tsunami risk area, evacuate at once: do not return until the tsunami warning or advisory is lifted
4. Switch off the breaker when you leave home: when you turn the power back on, first check cords and appliances for damage or scorch marks
5. Check on your family: leave a message on the 171 disaster message dial or web171 under the number you agreed in advance
6. Confirm information with official sources: use your municipality's evacuation information and the JMA, and do not pass on posts of unknown origin

Power-restoration fires tend to start just after electricity comes back. If you switch off the breaker before leaving, a fire is less likely to start while you are away. Deal with flames only after the shaking stops; the JMA also advises against trying to put out a fire while it is still shaking.

After a large earthquake, shaking of a similar strength may continue for some time. If the house is leaning or walls have large cracks, do not stay inside; move to a nearby evacuation site.

How to reach people when calls do not get through is covered in our column "Checking on family after a disaster: 171, web171 and the 00000JAPAN Wi-Fi", and what to check when your phone loses signal is in our no-signal article. False information and scams that circulate after earthquakes are covered in our column "False information and scams that follow disasters and big news: what to check before you share or donate".

When an Extra Information or subsequent-earthquake advisory is issued

The JMA issues two kinds of information when, after a large earthquake, the chance of an even larger one following is higher than usual. Neither is a prediction. Both mean "the chance is higher than normal, so review your preparations".

The first Nankai Trough Extra Information at the "Megaquake Advisory" level was issued on 8 August 2024. After an earthquake off Hyuganada at about 16:43 (M7.1, maximum seismic intensity lower 6), the JMA issued "Under Investigation" at 17:00 and "Megaquake Advisory" at 19:15. The government's call for special caution ended at 17:00 on 15 August. After the Hyuganada earthquake on 13 January 2025, "Under Investigation" was followed by "Investigation Concluded" at 23:45 the same day.

According to the JMA's record, the Hokkaido and Sanriku Subsequent Earthquake Advisory has been issued twice: on 9 December 2025 (after the previous day's earthquake east off Aomori, Mw7.4, maximum intensity upper 6) and on 20 April 2026 (after an earthquake off Sanriku the same day, Mw7.4, maximum intensity upper 5). Cabinet Office and JMA material notes that of 1,529 earthquakes of Mw7.0 or above worldwide, 19 were followed within a week by one of Mw7.8 or above: about 1%, or roughly ten times the usual frequency.

With either kind of information, the end of the caution period does not mean the risk has gone. Equally, a large earthquake can strike suddenly without any prior information. During the week after an advisory, aim to stay ready to move, for example:

• Keep shoes, a torch and your phone by the bed when you sleep
• Put your emergency bag by the front door or in the bedroom, and carry the essentials when you go out
• Recheck furniture fixings and escape routes; near the sea, walk the route to your evacuation site once
• Trips and events do not have to be cancelled, but check the evacuation sites at your destination before you go

For alerts other than earthquakes, such as missiles, see our column "When J-ALERT issues a ballistic missile warning: what to do outdoors, indoors and in a car".

What to agree on at home and at work

Preparation only works if family members and colleagues know about it too. Talking through the points below once at home and once at work will mean fewer moments of hesitation in the first hour after the shaking. For reading your local hazard map, our column "Official sources to check in a disaster: hazard maps, Kikikuru, evacuation info and outages" is a useful guide.