The short answer
A complaint is any grievance you report to the police. An FIR — First Information Report — is what the police must register when that grievance discloses a cognizable offence, meaning a serious one. The Supreme Court settled this in Lalita Kumari v. Government of UP (2014): on information about a cognizable offence, registration of the FIR is mandatory. Everything else travels a different track, through a Non-Cognizable entry and the magistrate.
What an FIR is
The FIR is the first information about a cognizable offence, recorded in writing under Section 173 of the BNSS (formerly Section 154 of the CrPC). It is not a finding, a charge, or a verdict — it is the written starting point of a police investigation. Once registered, it gets an FIR number, a copy goes to the magistrate, and the investigation begins. Because registration is mandatory for cognizable offences, a station cannot lawfully sit on it.
What a complaint means
Complaint is the everyday word for telling the police something wrong happened — in person, on paper, on a helpline, or on an online form. The term is also used formally for a complaint made to a magistrate. Either way, a complaint by itself does not start a police investigation; it is the raw material. What happens next depends on what the complaint discloses: a cognizable offence goes the FIR route, and the rest goes the non-cognizable route.
The non-cognizable track
For less serious matters, the police record a Non-Cognizable (NC) entry rather than an FIR. On an NC entry alone, the police cannot investigate without a magistrate's order — Section 174(2) of the BNSS (formerly Section 155(2) of the CrPC) says so expressly. In practice, that order is sought as an application to the magistrate under Section 175(3) of the BNSS (formerly Section 156(3) of the CrPC), asking the court to direct the police to register the case and investigate. This is the second track: complaint to NC entry to magistrate's order to investigation.
That online complaint form you filled
Online complaint forms on state police portals are petitions until an officer verifies them. Filling the form does not register an FIR by itself — someone has to read it, decide which track it belongs on, and act. Always save the acknowledgment or reference number the portal gives you, and follow up in writing at the police station if nothing moves. The written, stamped complaint remains the strongest record.
How to tell which track you are on
Ask the station — or check your paperwork — for which of these you actually have:
- An FIR number: you are on the FIR track. Investigation has started.
- An NC or General Diary entry number: you are on the non-cognizable track. Nothing investigates itself from here; the magistrate's route is the way forward.
- Only an acknowledgment or reference number: your complaint is still a petition. It has been received, not registered — follow up in writing.
A note on this guide
This is a description of the public process, not legal advice. For advice about your own case, speak to a lawyer or the police station handling it.