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Medical Subsidies for Children

Medical subsidies for children (子ども医療費助成, kodomo iryōhi josei) are municipal programs that reduce or eliminate a child's out-of-pocket share of medical costs already covered by Japan's national health insurance system.12 How generous a given program is, and at what age it stops, depends entirely on the city or ward administering it, which makes this one of the more consequential local differences to check before moving with children.

Confirm current details with official sources

Procedures, fees, and requirements can change. Confirm current details with your municipal (city or ward) child-welfare counter, since this program is administered locally; the Children and Families Agency (こども家庭庁) publishes the nationwide policy framework it sits within.

Overview

Japan's child medical expense subsidy system sits on top of, not in place of, national health insurance (国民健康保険) or employer-based health insurance.12 It does not pay for treatment itself. It reduces or removes the patient's statutory copayment share for treatment the underlying insurance already covers.

The generic term for this system is 子ども医療費助成 (kodomo iryōhi josei, "child medical expense subsidy"), though many municipalities use 乳幼児医療費助成 (nyūyōji iryōhi josei, "infant medical expense subsidy") for the youngest-age tier of the same program.12 Every prefecture and every municipality in Japan runs some version of this subsidy; there is no municipality without one (as of 2024-04-01, per the Children and Families Agency's most recent nationwide implementation survey).3 What differs sharply from place to place is how generous each program is: the age cap, whether an income limit applies, whether any copayment remains, and which of two payment mechanisms is used.

How subsidies work

Under Japan's health insurance law, a child's own statutory copayment share is 20% of the treatment cost from birth through the March 31 following their 6th birthday (that is, before elementary school entry), and 30% from elementary-school entry through age 69.4 This baseline is set by national law and does not change by municipality; only the subsidy on top of it does.

A municipal subsidy reduces or eliminates whichever of those two baselines applies to the child's age. Because the pre-elementary baseline is already lower, a subsidy that reduces both shares to ¥0 is waiving a smaller absolute amount before elementary school (20% to 0%) than it is afterward (30% to 0%).4

Subsidy programs are locally administered in layers: a prefecture typically funds a floor level of coverage, and the city, ward, or town on top of it may add its own budget to extend the age cap, remove an income limit, or absorb more of the copayment.567 Two payment mechanisms exist nationally to deliver that reduction: a point-of-service certificate that waives the copay at the clinic counter, and a reimbursement model where the resident pays first and claims the money back.82 Both are covered in detail in "Subsidy mechanisms" below.

Eligibility

Three separate tests determine whether a child qualifies for a given municipality's subsidy: age, residency, and health insurance enrollment. The age test is where the widest variation appears and is covered first.

Age caps by municipality

Age cap is the axis with the widest observed variation nationwide, and it is the central reason this topic matters for a family weighing where to live. A prefecture-level program sets a funding floor, and individual cities, wards, and towns within that prefecture routinely extend it much further using their own budgets.1567

MunicipalityOutpatient age capInpatient age capIncome limitCopayment at point of serviceMechanismAs of
Hyogo Prefecture (prefectural floor program)Through March 31 after turning 9 (3rd grade)SameYes, resident-tax income-levy threshold under ¥235,000 (no limit at age 0)Per-visit copay may still apply at this floor level; not itemized in the sourced pageNot specified in the sourced page2026-075
Itami City, Hyogo (mid-size city, pop. ~197,000)Through March 31 after turning 15 (middle school)Through March 31 after turning 18NoneAbsorbed to ¥0 by the city's own top-upCertificate2026-076
Ako City, Hyogo (small city, pop. ~46,000)Through age 18Through age 18None (city removed it)Absorbed to ¥0Certificate2026-077
Osaka CityThrough March 31 after turning 18SameNone (removed April 2024)Absorbed to ¥0Certificate, with reimbursement for out-of-area care2024-0429
Yokohama CityThrough middle-school year 3 (age 15); expanding to 18 from June 2026SameNone (removed August 2023)Absorbed to ¥0Certificate, with reimbursement for out-of-area care2023-08 / 2026-061011
Chuo Ward, TokyoThrough March 31 after turning 18 (マル乳→マル子→マル青 progression)SameNoneAbsorbed to ¥0Certificate, with reimbursement for out-of-area care2026-078
Minato Ward, TokyoThrough March 31 after turning 18SameNoneAbsorbed to ¥0Certificate, with reimbursement for out-of-area care2026-0712
Edogawa Ward, TokyoThrough March 31 after turning 18SameNoneAbsorbed to ¥0Certificate, with reimbursement for out-of-area care2026-0713

The figures above are current as of the dates shown in the table (as of 2026-07 for the Hyogo-area rows and Tokyo wards, and per the individual reform dates shown for Osaka City and Yokohama City; confirm current figures with each municipality's own child-welfare counter, since local budgets and age caps are revised on their own schedules). Treat Hyogo Prefecture's own program as a floor, not as a representative "conservative municipality": it is the funding base that Itami City and Ako City, the two Hyogo cities in this comparison, both build on top of with their own money. No comparably low-benefit program outside a prefectural floor itself could be sourced from an official municipal page during research for this article.

Income limits are disappearing, but unevenly

Osaka City removed its income limit in April 2024 and Yokohama City removed its in August 2023 (as of 2026-07), and both Hyogo cities in the table above have no income limit either. Hyogo Prefecture's own floor program still applies one. A family should check the specific municipality rather than assume the national trend has already reached every local program.910567

For historical context only, a Ministry of Health, Labour and Welfare survey covering fiscal year 2017 and published in 2018 found that the single most common municipal age cap nationwide was 15 (middle-school completion), at 58.7% of municipalities for outpatient care and 65.0% for inpatient care. That figure predates the wave of extensions to age 18 documented in the table above and should not be read as describing today's national picture.14

Residency and visa status

Eligibility turns on residency registration (住民票) in the municipality and enrollment in a health insurance plan, not on nationality. Municipal FAQs addressing foreign-national children state this explicitly.15

Foreign-resident children's residence records include their status of residence and period of stay, recorded on the same resident registration system used for the subsidy application.15 No source found in researching this article ties eligibility to a specific visa or status-of-residence category beyond that general residency-registration test.

Health insurance requirement

A child must already be enrolled in a public plan (National Health Insurance or a public employees' mutual aid plan) or an employer-based health insurance plan before a subsidy can apply. The subsidy tops up an existing insurance claim; it cannot apply to a child who is not insured.12

Coverage and what's not covered

Because the subsidy only tops up a copayment share on treatment the underlying health insurance already covers, anything that insurance itself does not cover is also not covered by the subsidy.1316 Municipal sources confirm the following are billed in full regardless of a subsidy certificate: private or upgraded hospital room fees (差額ベッド代), medication container fees (薬の容器代), document or certificate fees (文書料), routine vaccinations (予防接種), health checkups (健診料), and elective "selected medical services" beyond the standard insured treatment (選定療養費).1316

Traffic-accident injuries involving a third party, school or childcare-facility injuries covered by Japan's school mutual-aid insurance system, and costs already reimbursed under a separate high-cost-medical-expense benefit are also excluded, to avoid paying the same cost twice.1316

Hospital meal costs are not consistently covered

Whether standard inpatient meal costs (食事療養標準負担額) are covered varies by municipality and is not settled the same way everywhere. Tokyo's prefectural-level program frames meal costs as excluded by default, while Edogawa Ward's own program page states that it covers them (as of 2026-07). Confirm this specific point with the municipality's own program page rather than assuming either default, since an incorrect assumption can mean an unexpected bill.113

Application and subsidy certificate

Getting the certificate

A parent or guardian files the application at the ward or city office's child-welfare counter (often the same counter that handles child benefit / jidō teate), or by mail or online through the national My Number Portal ("ぴったりサービス") in the municipalities sourced for this article.8122

The documents required are consistent across the municipalities sourced here: the child's health insurance documentation (card or equivalent showing insurer, insured number, and enrollment date), the applying parent or guardian's identification, and in some municipalities an income or tax verification form, or a consent form allowing the office to check tax records electronically.81226 The certificate is not issued automatically at birth or on moving in; a parent or guardian must actively apply for it.12

Application windows vary by municipality and are not standardized nationally. Minato Ward specifies filing within 15 days of birth or moving in (as of 2026-07; confirm current figures with the ward's child-welfare counter), while Meguro Ward specifies within 3 months of birth or moving in (as of 2026-07).1217 These deadlines are similar in shape to, but administratively separate from, the 15-day exception in the national child benefit (jidō teate) program; meeting one program's deadline does not satisfy the other's.

A short application window can cost you months of coverage

Because the window for backdating coverage differs by ward, from as little as 15 days to as much as 3 months in the examples above, a family that assumes a generous window in one municipality can lose weeks or months of coverage after moving to a stricter one. Confirm the specific window at the new municipality's counter before relying on it.

Ako City's in-person processing time for issuing the certificate on the spot is approximately 20 minutes (as of 2026-07).7

Subsidy mechanisms

Two mechanisms exist nationally to deliver the subsidy: a point-of-service certificate that waives the copay directly at the clinic counter (現物給付方式, genbutsu kyūfu hōshiki), and a reimbursement model where the resident pays the copay and claims it back afterward (償還払い方式, shōkan barai hōshiki).82 These are not two separate categories of municipality. Point-of-service certificate use is the common in-area mechanism among the municipalities sourced for this article, and reimbursement is the fallback for out-of-area care or clinics that do not participate in the certificate scheme, making most sourced municipalities effectively hybrid: certificate in-area, reimbursement outside it.21318

TermReadingMeaning
医療証iryōshōThe medical certificate itself, presented at a clinic counter alongside the health insurance card.8
マル乳 / マル子 / マル青maru-nyū / maru-ko / maru-seiTokyo-area shorthand names for the infant, elementary/middle-school, and high-school-generation certificate tiers, named for a circle (◯, "maru") historically stamped on the certificate.812
現物給付方式genbutsu kyūfu hōshikiThe point-of-service mechanism: presenting the certificate waives the copay directly at the counter.2
償還払い方式shōkan barai hōshikiThe reimbursement mechanism: the patient pays the copay up front and later claims it back.2

The diagram below shows how the two mechanisms fit together in practice, using Edogawa Ward's own sourced reimbursement timeline as the concrete example.

Refund mechanism

Under the refund model, the resident pays the copay at the counter, then files a claim with the municipality: a receipt, health insurance documentation, guardian identification, and bank account details.18 From Edogawa Ward's own program description, the confirmed turnaround time to receive the refunded amount is approximately 2 months (as of 2026-07; confirm current processing times with the municipality).13

The filing deadline to submit a reimbursement claim is 5 years from the day after the medical payment date, a statute-of-limitations-style window consistent across the municipal sources that state it.1318

Keep receipts even after paying in full

A copay paid out of pocket is not lost money. As long as a reimbursement claim is filed within 5 years of the payment date, the copay can still be refunded, so it is worth keeping the receipt rather than assuming an unused certificate means a forfeited claim.1318

A child covered by health insurance issued outside Tokyo cannot use a Tokyo ward's certificate, even at a clinic located in Tokyo (as of 2026-07; a Tokyo-specific administrative rule tied to the current inter-prefectural claims-processing setup, not a statutory bar). The family must pay for care in that situation and then claim it back through the refund mechanism instead.1213

Point-of-service certificate mechanism

Presenting the medical certificate alongside the health insurance card at a participating in-area clinic waives the copayment directly at the counter, with no reimbursement claim needed.82 Municipalities use different names for the same underlying document: 医療証 in the Tokyo wards and Osaka, 受給者証 as a more generic term used by municipalities such as Ichinomiya City, and the locally branded maru-nyū / maru-ko / maru-sei tier names used in Tokyo.81215

Certificates are typically reissued on a fixed annual cycle in the Tokyo-ward examples sourced for this article; Meguro Ward's certificates renew on October 1 each year, with new certificates mailed the preceding September (as of 2026-07).16

Good to know

Moving between municipalities

A subsidy certificate is not portable between municipalities. Filing the standard moving-out residence notification automatically ends a child's subsidy eligibility as of the move date, no separate cancellation notice is required, and the certificate must be returned.19

The old certificate becomes invalid on the move date, and using it after that date can mean having to repay medical expenses later. A fresh application is required at the new municipality's counter to obtain a new certificate; coverage is not automatically transferred.1719

No official source describes a specific nationwide grace period that protects coverage continuity while a family is between municipalities. What is confirmed is narrower: the destination municipality's own general new-application deadline (for example, the 15-day and 3-month windows described above) is the only window that applies, and it functions as the de facto period to re-register without a coverage gap.

Out-of-area and emergency care

Where the certificate cannot be used (an out-of-prefecture facility, an out-of-Tokyo facility for a Tokyo resident, or any clinic that does not participate in the certificate scheme), the standard handling is to pay the insurance copay in full at the time of treatment and then file a reimbursement claim with the home municipality afterward.21318 This is the same reimbursement process described in "Subsidy mechanisms" above, not a separate emergency-specific procedure.

Osaka City residents specifically route out-of-Osaka claims through a dedicated Osaka Medical Subsidy Reimbursement Center, an example of a municipality centralizing this processing rather than handling it at the standard ward or branch counter (as of 2026-07).2 No source found in this research describes a wider-radius mechanism, such as a multi-prefecture reciprocal certificate network; the pay-then-claim reimbursement fallback appears to be the standard approach for out-of-area and emergency care generally, not an exception reserved for emergencies.

Coverage dates and timing

Coverage does not begin automatically at birth. It begins once the certificate is applied for and issued, and municipalities differ on how much of a backdating window they allow for a newborn or new arrival: 15 days in Minato Ward versus 3 months in Meguro Ward in the examples sourced for this article (as of 2026-07).1217 Applying after that window closes means losing subsidy coverage for the intervening months, even though the child was insured the whole time.

This backdating window is shaped similarly to, but is a fully separate administrative deadline from, the national child benefit (jidō teate) program's own 15-day exception, and from birth-registration or residence-status deadlines covered elsewhere. Meeting one program's deadline does not satisfy another's.

See also

References

Footnotes

  1. 東京都福祉局. 「乳幼児医療費助成制度(マル乳)」. https://www.fukushi.metro.tokyo.lg.jp/seikatsu/josei/marunyu 2 3 4 5 6

  2. 大阪市 (Osaka City). 「こどもの医療費を助成します」. https://www.city.osaka.lg.jp/kodomo/page/0000369443.html 2 3 4 5 6 7 8 9 10 11 12 13 14 15

  3. こども家庭庁 (Children and Families Agency). 「令和6年度『こどもに係る医療費の助成についての調査』」. https://www.cfa.go.jp/policies/boshihoken/kodomoiryouhityousa-r6

  4. 千葉市 (Chiba City). 「国民健康保険の医療費の自己負担割合について知りたいのですが。」(FAQ). https://www.city.chiba.jp/faq/hokenfukushi/iryoeisei/hoken/729.html 2

  5. 兵庫県 (Hyogo Prefecture). 「乳幼児等医療費助成事業」. https://web.pref.hyogo.lg.jp/kf07/hw06_000000004.html 2 3 4

  6. 伊丹市 (Itami City, Hyogo). 「乳幼児等・こども医療費助成制度について」. https://www.city.itami.lg.jp/SOSIKI/KENKOFUKUSHI/KOKI_IRYOF/HUKUSIIRYOSEIDO/1385628547589.html 2 3 4 5

  7. 赤穂市 (Ako City, Hyogo). 「乳幼児等医療費助成制度」. https://www.city.ako.lg.jp/kenkou/kokuho/nyuuyouji_jyosei.html 2 3 4 5

  8. 中央区 (Chuo Ward, Tokyo). 「子ども医療費助成」. https://www.city.chuo.lg.jp/a0020/kosodate/kosodate/teatejosei/iryouhijosei/akimoto.html 2 3 4 5 6 7 8 9

  9. 大阪市 (Osaka City). 「こども医療費助成制度の所得制限を撤廃しました(令和6年4月から)」. https://www.city.osaka.lg.jp/kodomo/page/0000597952.html 2

  10. 横浜市 (Yokohama City). 「小児医療費助成事業に所得制限はありますか。」(FAQ). https://www.city.yokohama.lg.jp/faq/kukyoku/kenko/kenko-iryou/20211015162144795.html 2

  11. 横浜市 (Yokohama City). 「小児医療費助成」. https://www.city.yokohama.lg.jp/kenko-iryo-fukushi/kenko-iryo/iryohijosei/shoni/

  12. 港区 (Minato Ward, Tokyo). 「子ども医療費助成」. https://www.city.minato.tokyo.jp/kosodatesien/kodomo/kate/kodomoiryo.html 2 3 4 5 6 7 8 9

  13. 江戸川区 (Edogawa Ward, Tokyo). 「子ども医療費助成制度」. https://www.city.edogawa.tokyo.jp/e049/kosodate/kosodate/teateshien/iryoujosei.html 2 3 4 5 6 7 8 9 10 11

  14. GemMed (Global Health Consulting Japan). "全都道府県・全市区町村で子ども医療費に何らかの助成、中には22歳まで助成する自治体も―厚労省." https://gemmed.ghc-j.com/?p=21391 (limitation: reports a FY2017 MHLW survey published 2018; cited only for structural/historical context, not current figures)

  15. 一宮市 (Ichinomiya City, Aichi). 「外国人の子どもですが、子ども医療費受給者証は申請できますか。」(FAQ). https://www.city.ichinomiya.aichi.jp/faq/1005664/1005974/1006740.html 2 3

  16. 目黒区 (Meguro Ward, Tokyo). 「子ども医療費助成制度とは」. https://www.city.meguro.tokyo.jp/kosodateshien/kosodatekyouiku/kosodate/toha.html 2 3 4

  17. 目黒区 (Meguro Ward, Tokyo). 「子ども医療費助成制度 こんなときは届出が必要です」. https://www.city.meguro.tokyo.jp/kosodateshien/kosodatekyouiku/kosodate/todokede.html 2 3

  18. koto-koto.jp. "Refund of Children's Medical Expenses Subsidy." https://koto-koto.jp/en/column/9291/ 2 3 4 5

  19. 一宮市 (Ichinomiya City, Aichi). 「他市へ転出(引っ越し)します。現在、子ども医療費受給者証を持っていますが手続きは必要ですか。」(FAQ). https://www.city.ichinomiya.aichi.jp/faq/1005664/1005974/1006724.html 2