| Code | Name | Region |
|---|---|---|
| JPYWA | Yawata | 12 |
| JPYWT | Yawata/kitakyushu | 40 |
| JPYWH | Yawatahama | 38 |
| JPYBK | Yobuko | 41 |
| JPYDG | Yodogawa-ku | 27 |
| JPYIC | Yoichi | 1 |
| JPYOC | Yoichigaura | 43 |
| JPYKK | Yokkaichi | 24 |
| JPYOK | Yokohama | 14 |
| JPZAL | Yokohama, Aomori | 2 |
| JPYKS | Yokoshima/kurahashi | 34 |
| JPYOS | Yokosuka | 14 |
| JPOKO | Yokota Apt/tokyo | 13 |
| JPYKT | Yokota, Hiroshima | 34 |
| JPYOO | Yokote | |
| JPYGJ | Yonago | 31 |
| JPOGN | Yonagunijima | 47 |
| JPYOG | Yonegura | 33 |
| JPYON | Yonezawa | 6 |
| JPYMG | Yamaguchi | 35 |
| JPYGH | Yamaguchihigashi | 35 |
| JPYNS | Yamanashi | 19 |
| JPYMN | Yamanoura | 43 |
| JPYTH | Yamashitacho | 14 |
| JPYMT | Yamatani | 32 |
| JPYIH | Yamato | 14 |
| JPWYA | Yamatokoriyama | 29 |
| JPYEA | Yame, Fukuoka | 40 |
| JPYAA | Yanagi | 43 |
| JPYAN | Yanai | 35 |
| JPYNI | Yani | 46 |
| JPYNN | Yanma | 46 |
| JPYAO | Yao | 27 |
| JPYHO | Yashio | 11 |
| JPYAU | Yasu | 25 |
| JPYSG | Yasugi | 32 |
| JPYAS | Yasumiya | 2 |
| JPYMA | Yasurahama | 46 |
| JPYTM | Yatomi, Aichi | 23 |
| JPWAH | Washimiya | 11 |
| JPWAT | Watanoha | 4 |
| JPHGG | Yabu | 28 |
| JPYBC | Yabuki-machi | |
| JPYCH | Yachiyo | 12 |
| JPYNE | Yaene | 13 |
| JPYAE | Yaeyama Island | 47 |
| JPYAG | Yagi, Hyogo | 28 |
| JPYGI | Yagi, Iwate | 3 |
| JPYGR | Yagishiri | 1 |
| JPYHK | Yahiko | 15 |