This is a translation of the Japanese original. The Japanese version is authoritative; figures follow Japanese tax law.
In 千葉県 (Chiba Prefecture), the "August 2026 Chiba torrential rain" (令和8年8月千葉豪雨) that began on 13 August has been followed by Typhoon No. 25 (台風25号) from 20 September, and homes are flooded and power is out again. Almost every payment and every tax or insurance-premium reduction that follows a disaster is decided by the damage category on the "disaster damage certificate" (罹災証明書). For flood damage that category is judged from the depth of the water, and 10 centimetres or more above floor level means "half destroyed" (半壊) or worse, which moves you up a step in both the support payments you qualify for and the size of the reductions. So the first job, before you start clearing up, is to photograph the height the water reached. This article sets out the municipalities covered by each of the two disasters, how to obtain the disaster damage certificate and the damage certificate for a car (被災証明書), the table linking water depth to damage category, and the amounts and deadlines for support payments, emergency repairs, disaster relief loans and municipal tax reductions, using material published by 千葉県 (Chiba Prefecture), 千葉市 (Chiba City) and the Cabinet Office (内閣府). The figures are as of 22 September 2026.
The short answer: the order to do things in, and what has a deadline
- Photograph before you clear up or repair. Outside, all four sides of the house, with a tape measure held against the water line so the height is legible, both wide and close up. Inside, a full view of each room plus close-ups of the damage.
- Apply to your municipality for the disaster damage certificate. A dwelling takes the disaster damage certificate (罹災証明書); a car, a shop or a shed takes the damage certificate (被災証明書). Judgement from photographs takes one to two weeks, an on-site survey two weeks to a month.
- Ask about municipal tax reductions without waiting for the certificate. A reduction requires an application by the payment due date; instalments whose due date has passed do not qualify (千葉市 / Chiba City).
- Once the certificate arrives, apply for the support payments, the solatium and the insurance-premium reductions together.
- On next year's tax return, use either the casualty loss deduction (雑損控除) or the Act on Reduction of Income Tax for Disaster Victims (災害減免法). Anything covered by insurance is deducted from the loss.
| Procedure | Deadline (as published by 千葉市 / Chiba City) |
|---|---|
| Municipal and prefectural resident tax reduction | By each payment due date (3rd instalment end of October, 4th end of January) |
| Fixed asset tax and city planning tax reduction | By each payment due date (3rd instalment 25 December, 4th end of February) |
| Disaster relief loan (災害援護資金) | Until three months have passed from the first day of the month after the disaster (around the end of November for the August rain; confirm the exact last day with your city) |
| Livelihood reconstruction support payment, basic portion | 13 months from the date of damage = 12 September 2027 (August rain) |
| Same, additional portion | 37 months from the date of damage = 12 September 2029 (August rain) |
| 千葉県 (Chiba Prefecture) disaster relief donations (for donors) | Collected until 30 November 2026 |
Sources: 千葉市 (Chiba City), "Municipal tax reductions relating to the August 2026 Chiba torrential rain"[Chiba City]; 千葉市, "Livelihood reconstruction support payments"[Chiba City]; 千葉市, "Disaster relief loans"[Chiba City]. Deadlines may differ in other municipalities.
Two disasters, two lists of municipalities: the August rain and Typhoon No. 25 are covered separately
The municipalities covered by the Disaster Relief Act (災害救助法) barely overlap between the August rain and Typhoon No. 25. Which of the two disasters your municipality is covered by decides which schemes you can use and which office guides you through them.
| August 2026 Chiba torrential rain | Typhoon No. 25, 2026 | |
|---|---|---|
| When | Evening of 13 August to the morning of the 14th. Over 360 mm in 千葉市 (Chiba City), the highest on record, with an emergency heavy rain warning | 20 to 22 September |
| Damage (published figures) | 13 dead and 46 injured; 6,220 homes damaged (2,183 flooded above floor level, 1,052 below) As of 12:00 on 9 September | 3 dead and 2 missing; 18 homes destroyed, 325 flooded above floor level (300 of them in 佐倉市 / Sakura City), 54 below Provisional figures as of 11:00 on 22 September |
| Disaster Relief Act | Applied from 13 August to 25 municipalities: 千葉市 (Chiba), 市川市 (Ichikawa), 船橋市 (Funabashi), 館山市 (Tateyama), 松戸市 (Matsudo), 茂原市 (Mobara), 佐倉市 (Sakura), 東金市 (Togane), 習志野市 (Narashino), 柏市 (Kashiwa), 市原市 (Ichihara), 八千代市 (Yachiyo), 我孫子市 (Abiko), 鎌ケ谷市 (Kamagaya), 四街道市 (Yotsukaido), 八街市 (Yachimata), 印西市 (Inzai), 白井市 (Shiroi), 大網白里市 (Oamishirasato), 富里市 (Tomisato), 山武市 (Sanmu), 酒々井町 (Shisui), 九十九里町 (Kujukuri), 白子町 (Shirako), 長柄町 (Nagara) | Applied from 20 September to 24 municipalities in all, including 銚子市 (Choshi), 木更津市 (Kisarazu), 野田市 (Noda), 成田市 (Narita), 旭市 (Asahi), 勝浦市 (Katsuura), 流山市 (Nagareyama), 鴨川市 (Kamogawa), 君津市 (Kimitsu), 富津市 (Futtsu), 袖ケ浦市 (Sodegaura), 南房総市 (Minamiboso), 匝瑳市 (Sosa) and 香取市 (Katori) |
| Act on Support for Reconstructing Livelihoods of Disaster Victims (被災者生活再建支援法) | Decided on 11 September for five cities: 千葉市 (Chiba), 佐倉市 (Sakura), 市原市 (Ichihara), 八千代市 (Yachiyo) and 大網白里市 (Oamishirasato). Other municipalities receive the same amounts through a prefectural scheme | No application published as of 22 September |
| Emergency repairs to housing | Under way (千葉市 plus 20 cities and 4 towns) | Nothing published as of 22 September |
Sources: Cabinet Office (内閣府), "Damage from the August 2026 Chiba torrential rain", report no. 15[Cabinet Office]; 千葉県 Disaster Response Headquarters, "Typhoon No. 25, 2026 (report no. 4)"[Chiba Prefecture]; 千葉県, "Application of the Disaster Relief Act"[August rain][Typhoon No. 25]; 千葉県, "Application of the Act on Support for Reconstructing Livelihoods of Disaster Victims"[Chiba Prefecture]
Typhoon No. 25 was still being surveyed as of 22 September. Application of the support Act and the start of emergency repairs are expected to be published in the coming weeks, following the same course as the August rain, but until they are decided they cannot be written up as settled schemes. If you were hit by the typhoon, there is nothing to wait for on the photographs and the certificate application: start both now.
Getting the certificate: 罹災証明書 for a dwelling, 被災証明書 for a car
The disaster damage certificate (罹災証明書) is the document in which the head of the municipality certifies how badly the home you live in was damaged, and it is required for almost every support payment, loan, reduction and emergency repair. The law requires a municipality that receives an application to survey the damage and issue the certificate "without delay" (Basic Act on Disaster Management, article 90-2)[Cabinet Office, criteria for assessing disaster damage].
| 罹災証明書 (disaster damage certificate) | 被災証明書 (damage certificate) | |
|---|---|---|
| Covers | The dwelling you actually live in | Everything else: offices, shops, warehouses, empty houses, gates and walls, carports and cars |
| What it certifies | The degree of damage (from "totally destroyed" to "partially damaged") | The fact that damage occurred |
| Photographs | All four sides of the exterior plus the height of the water; a full view of each room and close-ups of the damage | For a car: (1) the whole vehicle, (2) the damaged part, (3) the number plate |
| Fee | Free (千葉市 / Chiba City) | |
Sources: 千葉市 (Chiba City), "Issue of disaster damage certificates and damage certificates"[Chiba City]; 千葉県 (Chiba Prefecture), "About the disaster damage certificate"[Chiba Prefecture]
千葉市 (Chiba City) judges in three ways, and they take different lengths of time[Chiba City].
| Method | When it is used | Time to issue |
|---|---|---|
| Self-assessment (judged from photographs) | Where the damage is slight and you accept "partially damaged (under 10%)". Flooding below floor level, for example. No on-site survey | 1 to 2 weeks |
| Judgement from photographs | Where the depth of flooding can be confirmed from photographs | 1 to 2 weeks |
| On-site survey | The first survey covers only the exterior and the water depth. If you are not satisfied you can apply for a second survey that goes inside | 2 weeks to 1 month |
The application can be made by the head of the household or a member of the same household (an agent needs a letter of authority). Take your identification and the photographs to the temporary counter at your ward office, or, in 千葉市 (Chiba City), apply online (the person concerned only). Nothing is issued the same day. The city states plainly that a second survey can also lower the assessment, so showing the height of the water properly in your photographs is the surer route. There have also been warnings about people posing as surveyors and demanding a fee. City surveyors never charge.
Water depth decides the damage category: 10 centimetres above floor level is the dividing line
For flood damage, the Cabinet Office's operational guidelines set the loss ratio from the depth of the water. Where the outer walls and fittings are not broken, that is, ordinary flooding, the scale is as follows[Cabinet Office, operational guidelines for damage assessment, part 2: flood damage].
| Depth of water | Loss ratio | Damage category | Support payment |
|---|---|---|---|
| 1.8 m or more above floor level (or washed away) | 50% or more | Totally destroyed (全壊) | Basic ¥1,000,000 + additional up to ¥2,000,000 |
| 1 m or more but under 1.8 m above floor level | 40% to under 50% | Largely half destroyed (大規模半壊) | Basic ¥500,000 + additional up to ¥2,000,000 |
| 50 cm or more but under 1 m above floor level | 30% to under 40% | Moderately half destroyed (中規模半壊) | Additional only, up to ¥1,000,000 |
| Under 50 cm above floor level (10 cm or more above floor level) | 20% to under 30% | Half destroyed (半壊) | Basic ¥1,000,000 if the house is demolished. Qualifies for emergency repairs of ¥757,000 |
| Flooding below floor level | Under 10% | Partially damaged (short of "nearly half destroyed") | No support payment. Some solatium payments and reductions still apply |
千葉市 (Chiba City) advises that "flooding of 10 centimetres or more above floor level is assessed as half destroyed or worse, which increases the support schemes available to you and raises the amounts"[Chiba City, for those flooded above floor level]. Where the current or debris has broken the outer walls or fittings, the same depth moves up one category. Which is precisely why a photograph with a tape measure held against the water line on the wall decides the size of your support payment.
Money you can receive, and money you can borrow (2026 amounts)
| Scheme | Amount | Who qualifies, and on what terms |
|---|---|---|
| Livelihood reconstruction support payment, basic portion | Totally destroyed, half destroyed and demolished, or long-term evacuation: ¥1,000,000 / largely half destroyed: ¥500,000 | Three quarters of that for a single-person household. Outside the five cities the prefectural scheme pays the same. The municipality is the counter |
| Same, additional portion | Building or buying ¥2,000,000 / repairing ¥1,000,000 / renting ¥500,000 (for moderately half destroyed: ¥1,000,000, ¥500,000 and ¥250,000) | Once you apply for "repair" you cannot switch to "build or buy" later. Moving into public housing does not count as "renting" |
| Emergency repairs to housing (Disaster Relief Act) | Largely half destroyed to half destroyed: up to ¥757,000 / nearly half destroyed: up to ¥367,000 | A benefit in kind: the municipality pays the contractor directly. You receive no cash, and anything above the ceiling is at your own expense |
| Disaster relief loan (千葉市 / Chiba City) | Up to ¥3,500,000 if totally destroyed, ¥1,700,000 to ¥3,500,000 if half destroyed, ¥1,500,000 to ¥2,500,000 if a third or more of household goods were lost | Income conditions apply (under ¥4,300,000 for a two-person household, for example). Three-year grace period, 1% a year (interest-free with a guarantor), repaid over 10 years |
| Disaster condolence payment | ¥5,000,000 for the death of a household's main earner / ¥2,500,000 otherwise | Spouse, children, parents, grandchildren, grandparents (or siblings living in the same household if there are none) |
| Disaster disability payment | ¥2,500,000 for a main earner / ¥1,250,000 otherwise | Where a serious disability remains, such as loss of sight in both eyes |
| 千葉市 (Chiba City) disaster solatium | ¥50,000 if totally destroyed / ¥30,000 from half destroyed to nearly half destroyed | ¥30,000 even for "partially damaged" if the water came above floor level. Flooding below floor level does not qualify. Details are enclosed when the certificate is posted out |
Sources: 千葉県 (Chiba Prefecture), "Application of the Act on Support for Reconstructing Livelihoods of Disaster Victims and the prefectural support scheme"[Chiba Prefecture]; 千葉県, "Emergency repairs to housing"[Chiba Prefecture]; 千葉市 (Chiba City), "Disaster relief loans"[Chiba City]; 千葉市, "Disaster condolence payments"[Chiba City]; 千葉市, "Disaster solatium"[Chiba City]
The commonest misunderstanding about the support payment is "my city is not one of the five". 千葉県 (Chiba Prefecture) has announced that municipalities left outside the Act will receive the same amounts through a prefectural scheme. The other point is that a household assessed as "half destroyed" whose home was too dangerous to live in and was demolished qualifies for the same ¥1,000,000 basic payment as a totally destroyed home. Applications are made at the municipal counter; 千葉市 (Chiba City) is posting the forms to households that look likely to qualify.
Tax and insurance-premium reductions: what is past its due date does not come back
In 千葉市 (Chiba City) an application for a municipal tax reduction must be made "by the payment due date", and tax whose due date has passed, or that has already been paid, does not qualify. Instalments whose due date has not yet arrived at the time of the application are reduced even if you paid them early[Chiba City, municipal tax reductions]. Due dates arrive while you are waiting for the certificate to be issued. Talk to the municipal tax office first.
| Tax or premium | What is available (the 千葉市 / Chiba City example) |
|---|---|
| Individual municipal and prefectural resident tax | If the loss is half or more of the value of the home and household goods and your total income last year was ¥5,000,000 or less, the income-based portion is fully exempt. Half of it at ¥7,500,000 or less, a quarter at ¥10,000,000 or less. If the loss is three tenths or more, each of those is halved |
| Fixed asset tax and city planning tax (buildings) | Full exemption if totally destroyed, an 80% reduction if the value fell by 60% or more, and so on. For flooding above floor level, the share of the floor area damaged multiplied by four tenths |
| Automobile tax (prefectural) | Reduced in proportion to the period the vehicle cannot be driven. Guidance has been issued for cars damaged in the August rain |
| National Health Insurance, late-stage elderly medical care and long-term care premiums | As well as the premium reduction, the co-payment at medical institutions can be waived or deferred |
| National Pension premiums | Full exemption on application where roughly half or more of the home, household goods and the like were damaged |
| Deferral of payment | For municipal tax, payment in instalments within one year as a rule, partial waiver of late-payment charges and suspension of seizure. National taxes can also be extended or deferred on application to the tax office |
Sources: 千葉市 (Chiba City), "Municipal tax reductions"[Chiba City]; 千葉県 (Chiba Prefecture), "Prefectural tax reductions for disaster victims"[Chiba Prefecture]; 千葉市, "Payments and reductions for those affected"[Chiba City]; National Tax Agency (国税庁), "To everyone affected by the August 2026 Chiba torrential rain"[National Tax Agency]
Income tax is settled on next year's tax return. If the loss to your home and household goods (excluding anything covered by insurance) exceeds a tenth of your income, you can take the casualty loss deduction (雑損控除); if your income is ¥10,000,000 or less and the loss is half or more of the home and household goods, the Act on Reduction of Income Tax for Disaster Victims (災害減免法) reduces or waives your income tax. Which of the two works out better is calculated in choosing between the casualty loss deduction and the disaster reduction Act. The National Tax Agency has set up a dedicated page for the Chiba rain, and extensions of filing and payment deadlines and deferrals of payment are handled by individual application to your tax office.
One point for those on the giving side. 千葉県's disaster relief donations (until 30 November) qualify for the donation deduction, and there is no transfer fee if you pay in over the counter. You will need to file a tax return, so keep the transfer slip[Chiba Prefecture, disaster relief donations].
Seven things people miss
- A flooded car needs the 被災証明書. Three photographs including the number plate, issued free. It is used for the automobile tax reduction and the claim on your vehicle insurance.
- 10 centimetres above floor level is the line for "half destroyed". Hold a tape measure against the water line on the wall and photograph it. Flooding below floor level brings no support payment, but 千葉市's solatium pays ¥30,000 even for "partially damaged" if the water came above floor level.
- Insurance money is subtracted from the loss. For the resident tax reduction and the casualty loss deduction alike, anything covered by insurance does not count as a loss. Claim the flood cover on your fire insurance from the insurer with photographs and an estimate (whether they want the certificate varies by insurer).
- Fees for residence certificates and tax certificates are waived if you show the 罹災証明書. You will need them as attachments for the disaster relief loan and the like.
- Once you apply for the additional payment as "repair" you cannot change to build or buy. Decide whether you are repairing or rebuilding before you apply.
- Emergency repairs are not cash. The municipality pays the contractor directly. Anything above the ¥757,000 ceiling is at your own expense.
- Businesses go to a different counter. Shops and offices take the 被災証明書, and in municipalities covered by the Disaster Relief Act the chamber of commerce and others run special advice desks. What an employee can do at home in advance is collected in financial preparation before a typhoon.
Frequently asked questions
My home was flooded above floor level by Typhoon No. 25. Will I get the same support payments as for the August rain?
The Disaster Relief Act has applied to 24 municipalities since 20 September. The support Act and emergency repairs had not been published as of 22 September, but for the August rain they were decided about a month after the event. Start recording photographs and applying for the certificate now.
I rent. Do the certificate and the support payments apply to me?
Yes. The certificate covers the dwelling you actually live in, whether you own it or rent it. The livelihood reconstruction support payment also covers households in rented homes. A landlord qualifies only for a home they live in themselves.
Is there a deadline for the 罹災証明書?
The pages of 千葉市, 佐倉市 and 八千代市 state no application deadline (as of 22 September). The deadlines sit on the support schemes instead: municipal tax reductions run to each payment due date, and the disaster relief loan to three months from the month after the disaster. The sooner you get the certificate, the more schemes you can still use.
I was assessed as "partially damaged" and I disagree.
You can apply for a second survey, a detailed one that includes the inside of the house. You have to return the certificate you already received, and the second survey can lower the assessment. If you have photographs showing the height of the water, talk to the counter first.
Reference links (sources)
- 千葉市 (Chiba City), to everyone affected by the Chiba torrential rain — the entry point to the support schemes
- 千葉市, issue of disaster damage certificates and damage certificates — counters, photographs, the three methods of judgement and how long each takes
- Cabinet Office (内閣府), what to do first when your home is damaged (how to take the photographs)
- Cabinet Office, operational guidelines for assessing damage to dwellings, part 2: flood damage — water depth and damage category
- 千葉県 (Chiba Prefecture), application of the support Act and the prefectural livelihood reconstruction support scheme
- 千葉県, emergency repairs to housing (August 2026 Chiba torrential rain)
- 千葉市, municipal tax reductions / 千葉県, prefectural tax reductions / National Tax Agency, to everyone affected by the Chiba torrential rain
- 千葉県, on Typhoon No. 25, 2026 / application of the Disaster Relief Act (Typhoon No. 25) / Cabinet Office, damage from the August 2026 Chiba torrential rain
- 千葉県, recovery and support status (including advice desks for businesses)
Note: amounts are the 2026 figures and the damage counts are the values at the time of publication. Damage from Typhoon No. 25 and the support for it will be updated from here. Municipalities other than 千葉市 (Chiba City) set different reduction rates and deadlines, so check the guidance issued by the municipality where you live.
