In short. Ash is dangerous for jet engines, so during an eruption airlines cancel flights that cross the ash zone, even if Bali airport is working. Volcano status is on MAGMA Indonesia, and the aviation notices (VONA) are there too: orange code means a probable eruption with ash below 6,000 metres, red means higher. Under the Transport Ministry regulation, a cancelled flight entitles you to rebooking or a full refund, while the 300,000 rupiah compensation is not paid when the cause is weather or the airport. Do not go to the airport without a confirmed flight: airlines handle rebooking. If ash is falling on the ground, the Ministry of Health advises staying indoors, wearing an N95 respirator and goggles outside, and not riding a scooter.
Where the ash comes from. Bali is surrounded by volcanoes: its own Agung, Semeru, Bromo and Ijen on Java, Lewotobi Laki-Laki on Flores, and Anak Krakatau in the Sunda Strait. The wind decides where the ash goes, so an eruption a thousand kilometres away can close exactly your flight. In November 2017, during the Agung eruption, Ngurah Rai airport was closed: according to Anadolu Agency of 27 November 2017, the aviation code VONA was raised to red, the airport was shut for a day and thousands of tourists were stranded. On 7 July 2025, because of ash from Lewotobi, the airport counted 24 cancelled flights, mostly Jetstar and Virgin Australia to Australia, even though there was no ash in Bali's airspace (Antara). And on 6-7 September 2026 ash from Anak Krakatau cut Bali off from Java: according to the airport data as relayed by Kompas, 108 flights to and from Jakarta and Bandung were cancelled between 07:00 on Sunday and 11:00 on Monday, affecting about 13,000 passengers, while the airport itself worked normally. Smoke from forest fires acts in a similar way: in two months of autumn 2026 it disrupted 1,673 domestic flights in Indonesia, according to our news item of 12 October.
Where to check the status. The official platform is MAGMA Indonesia of the PVMBG volcanology centre: four activity levels from I (Normal) to IV (Awas), described in detail in the guide to volcanoes. For aviation, the same site keeps the VONA archive, the Volcano Observatory Notice for Aviation, with colour codes: green, the volcano is in its normal state; yellow, activity above background; orange, increased activity and a probable eruption with an ash column below 6,000 metres above sea level; red, an eruption is expected soon or is under way with ash above 6,000 metres. Each notice gives the time in UTC, the height of the cloud and the direction it is drifting. An orange or red code on a volcano along your flight's path is a reason to open the airline's app. The decision to cancel is made by the airline; the airspace is monitored by AirNav Indonesia together with the airport, and ash fall on the airfield itself is checked with sheets of paper laid on the apron, a "paper test" described by detikBali in 2025. Check your flight status in the app and in the email you gave when buying the ticket: the airport asks passengers to check before leaving for the airport. The airport information line works round the clock on 172.
What a passenger is entitled to. The rights are set out in Transport Ministry regulation PM 89/2015, which we covered in the guide to domestic flights. A cancelled flight is category six of delay: under article 9, the airline must move you to the next flight, including one of another airline, at no extra cost, or refund the full ticket price. A refund for a ticket paid in cash is given at once; for a ticket paid by card it is transferred within 30 calendar days. The compensation of 300,000 rupiah for a wait of more than four hours under article 6 is not due if the cause is outside the airline's control: weather, a closed airport or closed airspace. The regulation does not name ash on a separate line; it falls under these factors, and under article 5 the airline must confirm the cause with an official statement: from BMKG for weather or from the airport administration for a closure. You have the right to ask for this statement, and it is useful for your insurer. The regulation applies to Indonesian airlines on domestic flights; foreign carriers on international flights have their own rules and the rules of the departure country, so check the conditions of carriage in your ticket.
What to do on the day of a cancellation. The procedure the airport itself gave in July 2025: do not go to the airport without a confirmed flight, rebooking and refunds are handled by the airlines by email and in the app, and those already in the terminal are helped at the information desks. Our advice: keep all the airline's notifications and receipts for the hotel and food during the days of waiting. Insurers reimburse such costs under a policy with flight delay cover; check the terms in your contract and in the guide to health insurance. If you fly via Jakarta or Surabaya, do not buy the next ticket until the first is rebooked: separate tickets are not protected by anyone when a flight is cancelled. For Java and Lombok, when the sky is closed, the ferry and the overland route remain; the procedure is in the guide to the Bali-Java ferry.
Your visa when a departure falls through. A cancelled flight does not extend your visa: the stay is counted from the entry date, and every extra day after it ends is an overstay with a fine, see the guide to overstay. If your departure is in the last days of your visa, apply for an extension in advance at the first news of ash: since May 2025 you have to come to immigration in person for the photo and interview. Write to @buzz_visa on Telegram: we will tell you whether you are in time and arrange it.
Health: if ash reaches the ground. The advice comes from Indonesian Ministry of Health circular KL.01.02/A/17765/2026, issued in September 2026 during the Anak Krakatau ash, and the ministry's publication of 6 September. At home: close doors, windows and gaps, clean ash up wet and do not sweep it dry or blow it away, check the air conditioner filter, cover containers with water and food, and stock up on medicines if you have a chronic illness. Outdoors: an N95, KN95, KF94, FFP2 or equivalent respirator, or, if you have none, a medical mask as temporary protection; the mask must cover the nose, mouth and chin, and a wet or dirty one should be replaced; do not put masks on infants. Eyes: closed protective goggles, do not rub the ash, rinse with running water, and do not wear contact lenses during ash fall. Skin: long sleeves, trousers and closed shoes, and wash and change clothes after being outside. Transport: do not ride a scooter or travel in an open vehicle; when driving, slow down, turn on the lights and keep your distance. See a doctor or call 112 at once for a cough that does not stop, shortness of breath, chest pain, blue lips or fingers, eye pain and redness, or convulsions. The most vulnerable are children, the elderly, pregnant women and people with lung and heart conditions. The Ministry of Health hotline is Halo Kemenkes 1500-567.
What this means for you. Before a flight in a season of active volcanoes, open MAGMA and VONA and the airline's app; the airport board will show a cancellation last. If a flight is cancelled, ask for rebooking or a refund, get the statement of the cause for your insurer, and do not go to the airport without a confirmed flight. Extend your visa in advance with a margin so that ash does not turn into an overstay. If ash is falling outside, a day at home with the windows closed is better than any mask, and do not ride a scooter that day.