Buying land or a villa on Miyakojima, Irabu or Ishigaki: what foreign buyers must check (2026)

1. Security zones (Important Land Act): which areas are covered

Japan's Important Land Act (重要土地等調査法, Act No. 84 of 2021, fully in force 20 Sep 2022) lets the government designate land within roughly 1 km of defence and coast-guard facilities, and on remote border islands, as a watch zone (注視区域); the most sensitive ones are special watch zones (特別注視区域). The zones on Miyakojima and Ishigaki were designated by Cabinet Office Notice No. 98 of 12 Jul 2023, in force from 15 Aug 2023. Official

Irabu and Shimoji: there is no special watch zone on either island. Two watch zones touch them: the west coast of Shimoji (around Tori-ike and part of the airport) and the area around Nagayama port on Irabu. Shimojishima Airport as a whole is not a designated facility. But "Shimoji" on the main island is different: the former Shimoji town area (Kawamitsu, Uechi, near Maehama beach) is partly inside the special watch zone around the Miyakojima camp. Check the exact parcel on the official maps: Miyakojima overview map, district list, Shimoji zone map, Ishigaki overview map, Ishigaki district list, or the government's zone viewer. The district lists include districts only partly inside, so a district name alone does not tell you.

What it means for a buyer

• Watch zone: no permit or notification to buy. The government may collect information on owners and use (registries, and it can ask owners to report), and can advise and then order a stop to uses that would impair the facility (e.g. obstruction, radio interference); ignoring an order is a crime. Official
• Special watch zone: for land or buildings of 200 ㎡ or more (for buildings, total floor area), both seller and buyer must notify the Prime Minister (Cabinet Office) before signing, online (e-Gov) or by post arriving by the day before the planned contract date. Not notifying or a false notification: up to 6 months' imprisonment or a ¥1 million fine. The form changed on 1 Apr 2026. Official cao.go.jp
• Designation does not stop a sale, and there is no nationality ban. It is a disclosure and monitoring regime. Expect a broker to mention it in the statement of important matters (重要事項説明).

2. Water: Miyakojima lives on groundwater

• The whole of Miyakojima City is a groundwater-protection area. Under the city's Groundwater Conservation Ordinance (宮古島市地下水保全条例, 2009), pumping groundwater or drilling a well anywhere in the city needs the mayor's permit (Art. 11), with annual reporting. Official
• Wells on Shimoji and in Sarahama (north Irabu) are effectively not allowed. The city's groundwater plan classes them (with Ikema, Kurima and Ogami) as fragile small freshwater lenses at high risk of collapse from pumping, and grants no permits except small-scale farm use without fixed sprinklers. On the rest of Irabu, a prior geological and groundwater survey is required. So do not plan a pool or garden on your own well. Official
• Water-source protection areas (the Shirakawada, Higashi-Soedo-minami and Fukuzato-kita basins and part of the Hirara basin): golf courses, livestock, laundries, waste businesses and any facility with a septic tank for 51 or more persons (e.g. a larger villa complex or hotel) must consult the city first; if the city finds pollution risk it can declare the site a "regulated facility", which may not be built at all (Art. 20–21; up to 1 year in prison or ¥1 million). Official
• Irabu gets its tap water from Miyakojima, piped over the Irabu Bridge from the Sodeyama plant since Oct 2015; Irabu's own municipal wells are on standby. Press report Official
• Most villas need their own septic tank. Public sewers serve only part of Hirara: 15.3% of the city's population can connect (Mar 2022). Elsewhere a combined septic tank (合併浄化槽) is normal, and treated water soaks into the same limestone that holds the drinking water, so expect scrutiny of large systems. Official
• Ishigaki has no comparable island-wide groundwater ordinance; check with the broker whether the plot is inside the water-supply area and how far the main is (extension costs are yours). Our reading

3. Typhoons, wind and insurance

• On average 7.7 typhoons a year come within 300 km of a weather station in the Okinawa region (1991–2020 normal; Japan as a whole 11.7). Official
• The building code's design base wind speed for the whole of Okinawa is 46 m/s, the highest class in Japan (MLIT Notice 1454 of 2000). Most island homes are reinforced concrete for this reason; timber or container villas need a careful structural check, and shutters, roof fixings and outdoor units matter. Official
• Insurance: in Japan, typhoon wind damage is covered by standard fire insurance (火災保険, wind/hail cover); flood cover is optional and earthquake insurance is a separate add-on. Premiums depend heavily on structure (concrete is cheaper than timber). Get a quote before you buy, and check whether the insurer will cover a vacant holiday home. Our reading
• Also budget for salt damage to metal and air-conditioners, termites, and power and flight disruptions after storms. Our reading

4. Zoning, landscape, parks and farmland

• Landscape notifications are made before building; under the Landscape Act you may not start work until 30 days after the notification is accepted. Official
• Natural park: in special zones every building needs a permit; in ordinary zones a building over 13 m or 1,000 ㎡ floor area must be notified. The prefecture has been reviewing the Irabu park because of hotel development since the bridge (2015) and the Shimojishima terminal (2019) opened. Official Press report
• Red-soil ordinance: any land clearing or building work of 1,000 ㎡ or more must be notified to Okinawa Prefecture, and work may not start for 45 days. Official
• Farmland: much coastal land is registered as farmland. You cannot buy farmland as a non-farmer, and building on it needs conversion permission (農地転用); land inside an agricultural promotion zone must first be released from it, which is often refused. Farmland applications have recorded the buyer's nationality since Sep 2023. Official
• Large plots: buying 5,000 ㎡ or more inside a city-planning area (10,000 ㎡ outside, e.g. Irabu) must be reported to the prefecture within 2 weeks after the contract (National Land Use Planning Act). Official

5. Renting it out: Airbnb and licences

• Both cities fall under the Okinawa prefectural minpaku ordinance (2018, amended 2020), which names no restricted area in Miyakojima or Ishigaki. So a registered minpaku can operate up to the national cap of 180 nights a year anywhere on these islands. Official
• An overseas owner is always an absentee host and must appoint a registered minpaku management company (住宅宿泊管理業者). Year-round letting needs a ryokan-law licence (simple lodging), from the prefectural health centre (Miyako or Yaeyama). Because use zones cover only the towns, zoning rarely blocks it, but fire-safety, septic capacity and, on Miyakojima, the groundwater rules above do. Official Our reading
• Accommodation tax from 1 Feb 2027: 2% of the room rate, capped at ¥2,000 per person per night, including minpaku. In Miyakojima and Ishigaki it is split 0.8% prefecture + 1.2% city. Official
• Licences belong to the operator, not the building: buying a villa "with a licence" means applying again in your name. Full national rules: Airbnb rules by city.

6. New paperwork for foreign buyers

• Nationality at registration: from 5 Oct 2026 an individual registered as owner must declare nationality (with a passport copy if abroad). It is held internally and not shown on the public register. Official
• Foreign-exchange report: a non-resident who acquires Japanese real estate reports to the Minister of Finance through the Bank of Japan within 20 days. Holiday homes were always covered; since April 2026 homes bought to live in are too. An agent can file it. Official
• Special watch zone: the prior notification above, if 200 ㎡ or more.

7. Prices: a boom in a thin market

Official land prices show how fast this moved. On Miyakojima, residential standard land prices (基準地価, 2026-07-01) rose on average +7.8% in the latest year and the median point is up +98% over five years; the residential published prices (公示地価, 2026-01-01) rose +11.8%, after +16.0% a year earlier. Ishigaki: +5.9% (standard, latest year), +34% over five years. But Miyakojima's residential published prices fell every year from 2006 to 2017. An Irabu point that jumped +26.1% in 2024 rose only +4.7% in 2026. Official

Few transactions, many unsurveyed or farmland plots, and buyers from outside the island mean asking prices can run ahead of anything a later buyer will pay. Check boundaries (境界確定), road access, water and septic before paying for "sea view". Point-by-point official prices: Miyakojima & Ishigaki land prices. Our reading

8. Checklist before you sign

1. Is the parcel in a watch or special watch zone? (official map, parcel level) If special and 200 ㎡+, has the notification been filed before the contract?
2. Land category (地目): farmland? inside an agricultural promotion zone? Can it be converted?
3. Tap-water connection available? (Miyakojima: no private well unless permitted; not on Shimoji/Sarahama.) Septic capacity and discharge.
4. Landscape zone and height rule; natural-park zone (Irabu/Shimoji); red-soil notification if 1,000 ㎡+.
5. Road access, boundaries surveyed, flood/tsunami hazard maps.
6. Structure and typhoon resistance; insurance quote.
7. If renting out: minpaku (180 nights) or ryokan licence; management company; 2027 accommodation tax.

FAQ

Sources

1. Cabinet Office, Important Land Act: www.cao.go.jp; Okinawa zone list cao.go.jp; Notice No. 98 (2023, as amended) PDF; prior notification cao.go.jp; zone viewer www.resum2.go.jp
2. Miyakojima City Groundwater Conservation Ordinance PDF; 4th Groundwater Use Basic Plan (2021) ch.1 PDF, ch.3 PDF
3. Irabu water supply from Miyakojima (Miyako Mainichi, 30 Sep 2015): www.miyakomainichi.com; Okinawa Prefecture, Miyakojima sewerage: pref.okinawa.jp
4. Japan Meteorological Agency records: Miyakojima data.jma.go.jp, Ishigaki data.jma.go.jp; typhoon normals data.jma.go.jp
5. Base wind speed V0 (MLIT Notice 1454, 2000), table extract: www.biz-lixil.com
6. Miyakojima city planning city.miyakojima.lg.jp; Ishigaki city-planning area pref.okinawa.jp; City Planning Act e-Gov
7. Miyakojima Landscape Plan guideline (2021) PDF, notification table PDF; Ishigaki Landscape Plan city.ishigaki.okinawa.jp, plan text (2018) PDF; Landscape Act e-Gov
8. Irabu Prefectural Natural Park pref.okinawa.lg.jp; ordinary-zone notifications pref.okinawa.jp; review (Miyako Shimpo, 21 Oct 2022) miyakoshinpo.com
9. Okinawa Red Soil Erosion Prevention Ordinance pref.okinawa.jp; MAFF farmland acquisitions by foreign entities (2025) maff.go.jp; National Land Use Planning Act e-Gov
10. Okinawa minpaku ordinance summary PDF; Private Lodging Business Act e-Gov; Okinawa accommodation tax pref.okinawa.jp
11. Ministry of Justice notice No. 872 (nationality at registration from 5 Oct 2026) PDF; Ministry of Finance, reports on real estate acquired by non-residents mof.go.jp
12. Land prices: MLIT Land Price Publication and prefectural Land Price Survey via this site's land-price page (出典：国土交通省 不動産情報ライブラリのデータを加工して作成).