The Central Seat Allocation Board (CSAB) is the body that manages admissions to NITs, IIITs and other Government Funded Technical Institutes (GFTIs) after the main JoSAA counselling is complete. Its main job is to fill the seats that remain vacant after all JoSAA rounds — because of withdrawals, students not reporting, or failed document verification.

CSAB runs CSAB Special Rounds (usually one or two rounds). It is your last official chance to enter an NIT / IIIT / GFTI through the JEE Main merit list in that year.

CSAB special rounds begin only after the final JoSAA round is over. For 2026, CSAB officially starts on 28 July 2026. Registration and choice filling open from this date, and special rounds run over the following 1–2 weeks.

Round-wise deadlines are published on the official portal csab.nic.in. The moment CSAB publishes the official vacant seat matrix, the clock starts — and you only get a short window to register and fill choices.

CSAB uses the same JEE Main rank, category and quota logic as JoSAA. After JoSAA closes, all unfilled NIT/IIIT/GFTI seats are pooled into a vacant seat matrix. You fill a fresh preference order from these vacant seats, and CSAB allots seats by merit, category and your choices.

Two quota concepts matter a lot in CSAB: Home State (HS) seats for the state where you did your 12th, and Other State (OS) / All India (AI) seats. Female-only supernumerary seats also apply.

There are two common situations:

• You keep your JoSAA seat and also try CSAB: If CSAB allots you a new (better) seat and you accept it, your old JoSAA seat is automatically cancelled and you shift to the new institute.
• You get nothing better in CSAB: Your original JoSAA seat stays safe as long as you completed JoSAA reporting/fee correctly and did not withdraw.

This is exactly why CSAB is a low-risk upgrade opportunity — but the choice order matters a lot, because once a better seat is allotted, you cannot go back to the old one.

There are two different fees in CSAB:

• CSAB registration / processing fee: A separate, non-refundable fee you pay when you register for CSAB special rounds. This is in addition to what you paid in JoSAA.
• Seat acceptance fee: The seat acceptance fee you already paid during JoSAA is generally carried forward / adjusted in CSAB — you usually do not pay the full seat fee twice. If any partial fee applies, it is shown at the time of allotment.

Refund and adjustment rules (and the exact fee amounts) are published every year in the official CSAB business rules / brochure. Always confirm the current-year numbers on csab.nic.in.

Explore the full 2025 CSAB special-round vacant seat list — 105 institutes and 13,700+ vacant seats. Search an institute (type 2–3 letters, e.g. "bhopal" → IIIT Bhopal), and filter by quota, category and seat pool. Use it as a reference to understand what kind of seats open up in CSAB.