Why You Shouldn't Judge an IPO by Day One: How Subscription Really Builds
By IPO Cracker Editorial Team · 08 Sept 2026
An IPO shows "1.2x subscribed" on day one and everyone assumes it's off to a slow start. We pulled the day-by-day subscription snapshots for every closed and listed IPO we've tracked and measured exactly how much of the final number is actually visible on day one — and how much shows up only on the last day of bidding.
The method
For every IPO with at least two distinct days of subscription snapshots, we took the last recorded total-subscription reading for each bidding day (day 1, day 2, and so on through close) and compared day one's reading and the final day's reading against the eventual final multiple. That gives 58 Mainboard IPOs and 93 SME IPOs with a usable day-wise trail.
The headline result
| Segment | IPOs | Avg % of final subscription visible on Day 1 | Avg % added on the closing day |
|---|---|---|---|
| Mainboard | 58 | 7.3% | 82.4% |
| SME | 93 | 15.9% | 67.5% |
On the average Mainboard IPO, barely a fourteenth of the eventual demand has shown up by the end of day one — and more than four-fifths of the entire subscription arrives on the closing day alone. SME issues build more evenly across the bidding window, but even there, more than two-thirds of final demand lands on the last day.
Why the last day dominates
Three structural reasons drive this. QIB (institutional) bidders can only bid on the first two days of a Mainboard issue and tend to place their orders late in that window rather than early, once they've watched retail and grey-market sentiment build. NII (HNI) investors, who often borrow to fund large applications, deliberately wait until the closing day to minimise the number of days their money — or their loan — is tied up. And retail sentiment itself compounds through the week: a rising GMP or a strong day-two number draws in applicants who were waiting to see confirmation before committing.
SME issues show a less extreme pattern partly because they have no separate QIB-only bidding window in the same way, and partly because SME demand is more often driven by a smaller, more decisive pool of dedicated SME investors who don't wait for confirmation the way first-time retail applicants do.
What to do with this
- Don't write off a Mainboard IPO from its day-one number. A 1-2x reading on day one is normal, not a warning sign — the real test is where GMP and the QIB book stand as day two and three unfold.
- Watch the QIB window specifically on Mainboard issues. Since institutions bid mainly in the first two days and typically late in that window, a weak QIB book by the end of day two is more informative than a weak retail number on day one.
- For SME issues, early numbers carry a bit more weight — they represent a larger share of the eventual total than on Mainboard, though the majority of demand still arrives on the last day.
The honest caveats
The "day" number here is computed from the gap between the recorded snapshot date and the IPO's opening date, which can be thrown off by a day if a scrape lands right at midnight or an exchange posts a snapshot late. IPOs with only a single subscription snapshot were excluded entirely, which slightly biases the sample toward issues we tracked more closely. And this describes the average pattern — plenty of individual IPOs, especially high-demand ones, subscribe fully well before the final day.
Track the day-wise subscription build for any currently open IPO on its live page, which shows the same day-by-day table this analysis is built from.