DIN vs DPIN vs CIN vs LLPIN — What Each Number Actually Identifies
DIN, DPIN, CIN, and LLPIN are four identification numbers that show up constantly in Indian company and LLP filings, and they’re often used loosely as if interchangeable. They’re not. The simplest way to keep them straight: two identify a person, two identify an entity, and one of the four (DPIN) no longer exists as a distinct number at all.
The Core Distinction: Person vs Entity
| Number | Identifies | Format |
|---|---|---|
| DIN (Director Identification Number) | An individual who is, or intends to become, a director of a company | 8-digit number |
| DPIN (Designated Partner Identification Number) | Historically, an individual designated partner of an LLP — now merged into DIN | Was 8-digit; now simply a DIN |
| CIN (Corporate Identification Number) | A company, on incorporation | 21-character alphanumeric code |
| LLPIN (LLP Identification Number) | A Limited Liability Partnership, on incorporation | 7-character alphanumeric code |
A director or designated partner carries a DIN with them across every company or LLP they’re associated with — it doesn’t change when they join a new company. A CIN or LLPIN, by contrast, belongs permanently to the entity itself and never transfers, even if the entity changes its name, registered office, or activities.
DIN: Director Identification Number
Every individual who wishes to be appointed as a director of any Indian company must first obtain a DIN, allotted by the Central Government through the MCA. It’s an 8-digit number, allotted once to an individual for life (barring surrender or deactivation), and used across every company that individual is or becomes a director of. See Form DIR-3: Application for Allotment of DIN for the allotment process.
A DIN doesn’t expire, but it can be deactivated for non-filing of KYC — see the DIN KYC Due Date Calculator for the current filing cycle and DIR-3-KYC-Web for the filing itself.
DPIN: Designated Partner Identification Number (Now Obsolete as a Separate Number)
Under the original LLP framework, a designated partner of an LLP was required to obtain a DPIN, structurally parallel to a director’s DIN. That distinction was subsequently removed — DPIN has been merged into DIN, and today a single DIN serves both purposes: a person holding a DIN can be appointed as a company director and/or an LLP designated partner using the same number. References to “DPIN” that persist in older documents, forms, or informal usage should be read as referring to what is now simply a DIN.
This is a common point of confusion for anyone reading slightly older LLP documentation, incorporation checklists, or forms that still use the DPIN terminology — the number itself hasn’t disappeared, it’s just no longer issued or tracked as a category separate from DIN.
CIN: Corporate Identification Number
A CIN is a 21-character alphanumeric code assigned by the Registrar of Companies to every company on incorporation. Unlike a DIN, which identifies a person, a CIN identifies the company itself and never changes for the life of that entity, regardless of changes in name, registered office state, or business activity — the CIN encodes information at the point of incorporation (listing status, industry code, state, year, ownership type, and a sequential registration number), and that history stays embedded in the code even after later changes.
For the detailed structure of a CIN — what each segment of the 21 characters represents — see State Codes and CIN Format Guide.
LLPIN: LLP Identification Number
An LLPIN is the equivalent identifier for a Limited Liability Partnership — a unique alphanumeric number assigned to every LLP on incorporation, structurally shorter than a CIN. It identifies the LLP as an entity, distinct from the DIN of any individual designated partner.
Why the Distinction Matters in Practice
Mixing these up isn’t just a terminology slip — it causes real filing errors:
- A form asking for a director’s identification expects a DIN, not the company’s CIN, and vice versa. Entering the wrong number in the wrong field is a common cause of rejected or defective filings, particularly on forms with several signatory fields.
- A person’s DIN stays the same across every company they join or leave — it is not regenerated or reissued, and should not be confused with a new company’s CIN just because the person recently joined that company as a director.
- A company’s CIN changes in one specific circumstance: when the company’s listing status, activity classification, or registered-office state changes in a way that affects the embedded CIN segments, the Registrar issues a new CIN, even though the company’s legal identity and incorporation date remain unchanged. This is one of the only situations where an entity’s identification number is not, in fact, permanent for the entity’s entire life — worth knowing so a “changed CIN” isn’t mistaken for a new company.
- An LLP looking to convert into a company, or vice versa, will end up with both an LLPIN (for its LLP existence) and, on successful conversion, a CIN (for its company existence) — the two numbers track two different legal identities of what a layperson might think of as “the same business,” across a conversion event. See LLP Form No. 18: Conversion of a Company into an LLP for that specific conversion direction.
Quick Reference
- Looking up a person’s directorship history? You need their DIN.
- Looking up a company’s registration details? You need its CIN.
- Looking up an LLP’s registration details? You need its LLPIN.
- Someone mentions a “DPIN”? They mean a DIN — the terms have effectively merged, and only DIN is issued today.
Key Takeaways
- DIN and DPIN identify a person; CIN and LLPIN identify an entity — this is the fundamental distinction to hold onto when any of the four terms come up.
- DPIN no longer exists as a separately issued number — it has been merged into DIN, and a single DIN now covers both company directorship and LLP designated partnership.
- A CIN is ordinarily permanent for the life of the company, but is reissued if the embedded classification (listing status, activity, or state) changes — a rare but real exception to “the number never changes.”
- Entering a person’s DIN where an entity’s CIN or LLPIN is expected (or vice versa) is a common, avoidable cause of filing errors on MCA forms.