Why B-HNI Allotment Odds Are Nearly 5 Times Better Than the Formula Suggests
By IPO Cracker Editorial Team · 03 Aug 2026
Almost every allotment calculator uses the same formula: your chance is 1 divided by the subscription multiple. For Retail and Small HNI that is close enough. For Big HNI it is wrong by roughly five times, and the reason is a SEBI rule most calculators ignore.
The rule that breaks the formula
SEBI splits the Non-Institutional Investor category in two. Small NII covers applications between Rs 2 lakh and Rs 10 lakh. Big NII covers applications above Rs 10 lakh, and is reserved two-thirds of the NII portion.
Here is the part that matters. A B-HNI must bid above Rs 10 lakh, but SEBI requires that allotment to each NII be not less than the minimum bid lot. So a B-HNI is allotted the same minimum NII lot an S-HNI receives.
Applications enter at Rs 10 lakh. Allotments leave at Rs 2 lakh. That pool therefore reaches about five times more applicants than dividing by the subscription multiple implies.
What a real basis of allotment shows
This is measurable, not theoretical. A published basis of allotment document reports both applications received and allottees per category. Comparing them against the naive formula:
| Category | Formula estimate | Actual odds | Correction factor |
|---|---|---|---|
| Retail | 14.39% | 16.37% | 1.14x |
| S-HNI | 2.74% | 2.79% | 1.02x |
| B-HNI | 1.99% | 9.59% | 4.83x |
The same document states that shares allotted per bidder were identical for S-HNI and B-HNI, which is exactly what the minimum-lot rule requires. B-HNI applicants faced odds nearly five times better than the formula predicted.
Why the factor is not always 4.83
The ratio is Rs 10 lakh divided by Rs 2 lakh, adjusted for lot rounding, so it shifts slightly with the lot value of each issue. On another issue in the same period it worked out to 4.93. Any calculator quoting a single fixed factor is approximating; the honest version computes it from the issue lot value.
Retail needs a smaller correction too
Retail came in at 16.37% against a 14.39% estimate, a factor of about 1.14. Many retail investors apply for more than one lot, so applications overstate the number of distinct lot-claims slightly. S-HNI needed essentially no correction at 1.02.
QIB is a different mechanism entirely
QIB allotment is proportionate, decided by the merchant banker, not a draw of lots. In the same document all 101 QIB applicants received an allotment. A chance of allotment is not a meaningful concept for QIB, and any calculator quoting one for it is applying the wrong model.
What this means practically
- If you are near the Rs 10 lakh boundary, the category you land in matters enormously. Crossing into B-HNI can improve your odds several times over.
- Distrust any calculator that treats every category with 1 divided by x. It systematically understates B-HNI.
- Read the basis of allotment after the fact. It is the only document that reports what actually happened rather than an estimate.
None of this is a recommendation to bid above Rs 10 lakh. Better odds on a larger commitment is not the same as a better investment, and a listing loss on a Rs 10 lakh application hurts considerably more than on Rs 15,000.
Our allotment chances calculator applies these corrections using each issue lot value. Method and measured figures: how we calculate allotment odds.