Do CSAB Choices Carry Forward From SR1 to SR2?

CSAB's two special rounds — SR1 and SR2 — are not independent cycles that each require their own registration and choice-filling. They run off a single common registration and a single locked choice list, submitted once before SR1 begins. This is one of the most important structural differences between CSAB and JoSAA for candidates to internalize: JoSAA gives you five separate rounds, often with choice-editing windows between them, while CSAB compresses everything into one registration and locking event followed by two allotment runs against that same list.

In practice, this means you do not need to re-register for SR2, you do not need to re-fill or reorder your choices, and any preference in your original list that wasn't allotted to you in SR1 automatically remains "live" and gets re-evaluated against the SR2 seat pool. The system essentially re-runs the same allotment logic a second time, using the same list, but against an updated (and usually smaller, though sometimes partially replenished) set of available seats.

The One Thing That Does Not Carry Forward: Frozen Seats

The single major exception to "everything carries forward" is what happens after you Freeze a seat in SR1. Freezing is treated as a final decision — once you freeze and complete the required fee payment and reporting steps, you exit the centralized allotment process entirely and are not evaluated again in SR2, even though your original choice list is technically still on file. This is why the decision to Freeze versus Float in SR1 carries more weight in CSAB than the equivalent decision in any single JoSAA round: it's effectively your last opportunity to keep your options open for a further upgrade.

Because there's no re-filling or reordering of choices between SR1 and SR2, the single locked list you submit before SR1 has to do double duty — it needs to reflect every institute-branch combination you'd genuinely accept, ranked in a realistic order, since you won't get a second chance to add options you left out. Candidates who fill a narrow list expecting to "add more later" in SR2 are working from an incorrect assumption; there is no later choice-filling step.

Since unfilled preferences from SR1 automatically remain active for SR2, there's little practical value in trying to game the system by leaving weaker options off your list to "force" a better outcome — including a broad, honestly-ranked list only helps you, since being evaluated against a preference doesn't cost you anything unless it's actually allotted and you accept it.

The most consequential decision point in this entire two-round structure is therefore your Freeze-versus-Float choice after SR1. If you freeze, you're finished — SR2 will not run for you at all, regardless of what's in your locked list. If you float, your full list (minus whatever you were already offered in SR1, if that's your new floor) gets a second look during SR2's allotment run automatically, with no extra effort required from you beyond monitoring your registered login for the SR2 result.

Consider a candidate who registers for CSAB, fills a list of fifteen institute-branch preferences spanning a mix of NITs, IIITs, and GFTIs, and locks that list ahead of the SR1 deadline. When SR1 results are declared, suppose this candidate is allotted their eighth-ranked preference — reasonably good, but not their top choice. If they choose Freeze, their journey through CSAB ends here: SR2 will not evaluate them again, and their remaining seven higher preferences (ranks one through seven) simply become irrelevant, even though they're technically still sitting in the locked list on file.

If instead this candidate chooses Float, all seven higher preferences remain "live" going into SR2. The SR2 allotment engine automatically checks whether any of those seven better options have become available — perhaps because another candidate who held one of those seats froze elsewhere, or a seat that was allotted in SR1 went unpaid and was released. If one of those better preferences opens up, the candidate is automatically upgraded to it. If none do, the candidate simply retains their original eighth-ranked seat from SR1 — there is no scenario where floating causes them to lose the seat they already have.

This example also illustrates why building a genuinely long, well-considered list before locking matters so much in CSAB specifically. A candidate who only filled five preferences instead of fifteen would have far fewer "live" options carrying into SR2 if they float, and a much higher chance of ending SR1 with no allotment at all if none of those five narrow choices matched. Since there's no opportunity to add more preferences once locked, erring toward a broader list — spanning realistic, aspirational, and safety options — consistently produces better outcomes across both CSAB rounds than a narrowly curated one.