If you are on one of the more expensive injectable treatments, your medical costs in a given month can climb. The High-Cost Medical Expense Benefit (高額療養費制度, kōgaku ryōyōhi seido) sets a monthly ceiling on your out-of-pocket costs and refunds anything above it.
What the scheme is
Japan's public health insurance places an upper limit (限度額, gendogaku) on how much you pay out of pocket in a single calendar month. Anything above that limit is refunded to you when you apply. That is the High-Cost Medical Expense Benefit.
The limit depends on your age and income. Most people with osteoporosis are 70 or older, so the explanation below focuses on the scheme as it applies from age 70.
Monthly out-of-pocket caps for people aged 70 and over — the system from August 2026
The High-Cost Medical Expense Benefit was revised from August 2026 (stage 1). In August 2027 the income categories will be subdivided further (stage 2, described below). The caps below apply from August 2026 through July 2027.
| Income category |
Outpatient (per person) |
Outpatient + inpatient (household total) |
Annual cap (August to the following July) |
| General (annual income up to approx. ¥3.7 million) |
¥22,000 (outpatient annual cap ¥216,000) |
¥61,500 |
¥530,000 (¥410,000 if annual income is under approx. ¥2 million) |
| Working-age-equivalent I (annual income approx. ¥3.7–7.7 million) |
— |
¥85,800 + (total medical cost − ¥286,000) × 1% |
¥530,000 |
| Working-age-equivalent II (annual income approx. ¥7.7–11.6 million) |
— |
¥179,100 + (total medical cost − ¥597,000) × 1% |
¥1,110,000 |
| Working-age-equivalent III (annual income above approx. ¥11.6 million) |
— |
¥270,300 + (total medical cost − ¥901,000) × 1% |
¥1,680,000 |
| Exempt from resident tax (住民税非課税) |
¥11,000 (outpatient annual cap ¥96,000) |
¥25,700 |
¥290,000 |
| Exempt from resident tax, income below a set level |
¥8,000 |
¥15,700 |
¥180,000 |
"Outpatient (per person)" is the cap that applies if you have only outpatient visits. In a month that includes a hospital stay, the "household total" cap applies instead. The reduced cap for frequent users (多数回該当: from the fourth month in any twelve in which you reach the cap) is unchanged at ¥44,400 for the general and working-age-equivalent I categories and ¥24,600 for those exempt from resident tax.
For reference, through July 2026 the general category paid ¥18,000 outpatient (¥144,000 a year) and ¥57,600 household total; those exempt from resident tax paid ¥8,000 outpatient and ¥24,600 household total (¥15,000 if income was below the set level).
What changed in the August 2026 revision
The amounts changed, but the way you use the scheme stays the same: the eligibility certificate or your My Number health insurance card still works. Here is what changed.
Stage 1 (from August 2026)
- The monthly caps rose in every income category (for example, for people aged 70 and over in the general category, outpatient ¥18,000 → ¥22,000 and household total ¥57,600 → ¥61,500). The only cap left unchanged is the ¥8,000 outpatient cap for people exempt from resident tax with income below the set level.
- The reduced cap for frequent users is frozen, so people who have been in treatment for a long time do not pay more.
- A new annual cap was introduced. Once your out-of-pocket total for the year (August to the following July) reaches the annual cap (¥530,000 in the general category), anything beyond it is refunded by your insurer. This also covers people whose monthly bills never reach the monthly cap.
- An outpatient annual cap of ¥96,000 now applies to people exempt from resident tax, so someone who pays up to the monthly cap every month pays no more over the year than before.
Stage 2 (planned for August 2027)
- The five income categories become thirteen. For people aged 70 and over in the general category, the outpatient cap stays at ¥22,000 up to approx. ¥2 million of annual income and becomes ¥28,000 for approx. ¥2–3.7 million (the ¥216,000 outpatient annual cap is shared). The household total becomes three steps: ¥61,500, ¥65,400 and ¥69,600.
- The reduced cap for frequent users falls from ¥44,400 to ¥34,500 for people with annual income under approx. ¥2 million.
- The outpatient cap for people exempt from resident tax becomes ¥13,000 (annual cap ¥96,000).
For people with a long-term condition like osteoporosis, where treatment continues for years, the new annual cap and the frozen frequent-user cap are the parts that matter most when you look at a whole year at a time.
What to do is unchanged
Even with the revisions, the steps are the same:
- Get an eligibility certificate in advance (or use your My Number health insurance card)
- Read the notices from your insurer. A refund under the annual cap may require an application
- Talk to your doctor if you are worried about cost
The figures above are taken from the Ministry of Health, Labour and Welfare's published materials (updated July 2026). Check your own category and amounts in the notices from the insurer you are enrolled with: National Health Insurance (国民健康保険, kokumin kenkō hoken), your employer's health insurance society (健康保険組合, kenkō hoken kumiai), or the regional association for late-stage elderly medical care (後期高齢者医療広域連合, kōki kōreisha iryō kōiki rengō).
How to use the High-Cost Medical Expense Benefit
Option 1: Apply after the fact (pay in full first, get refunded later)
- Pay as usual at the medical institution
- Later, your insurer (health insurance society, National Health Insurance, and so on) sends you information about applying for the benefit
- Once you apply, the amount above your cap is transferred to your bank account (in two to three months)
Option 2: Certificate of Eligibility for the Ceiling Amount (never pay more than the cap in the first place). We recommend this option.
The certificate is called the 限度額適用認定証 (gendogaku tekiyō ninteishō). It is a card you show at the counter so you are only ever billed up to your monthly cap.
- Apply to your insurer for the certificate in advance
- Show the certificate at the billing counter (会計窓口, kaikei madoguchi) of the hospital or clinic
- You pay only up to your cap from the start
Our recommendation: get the certificate before you start an expensive medication, and you will have one less thing to worry about. If you have a My Number health insurance card (マイナ保険証, maina hokenshō: your My Number card registered for use as a health insurance card), the cap is often applied automatically without any certificate.
When the benefit helps most
- A month in which you receive a higher-cost injectable treatment: this can come to about ¥25,000–30,000 at the 30% rate → anything above your cap comes back
- A month in which you are admitted for surgery: surgery plus hospital stay can run to several hundred thousand yen → you pay only up to your cap
- A month in which you are treated at more than one hospital or clinic: the costs are combined, and if the total exceeds your cap it qualifies