Jainagar is Taluka (Tehsil) in Madhubani district of Bihar state. Jainagar has 9 areas (postal offices).
| Pin code | Area | District | Taluka | Postal Status |
|---|---|---|---|---|
| 847226 | Bela PIN Code | Madhubani | Jainagar | Branch Office |
| 847226 | Chachraha PIN Code | Madhubani | Jainagar | Branch Office |
| 847226 | Deodha PIN Code | Madhubani | Jainagar | Branch Office |
| 847226 | Dullipatti PIN Code | Madhubani | Jainagar | Branch Office |
| 847226 | Jaynagar PIN Code | Madhubani | Jainagar | Sub Office |
| 847226 | Jaynagar Bazar PIN Code | Madhubani | Jainagar | Sub Office |
| 847226 | Kamalabari PIN Code | Madhubani | Jainagar | Branch Office |
| 847226 | Nil PIN Code | Madhubani | Jainagar | Branch Office |
| 847226 | Uchhal PIN Code | Madhubani | Jainagar | Branch Office |