You appoint an auditor at your AGM. You tell the ROC about it through ADT-1 filing. That intimation is due within 15 days of the AGM — October 15 for companies whose AGM was on September 30. Miss it, and the penalty meter starts ticking at Rs.100 a day.

Most companies get the appointment right but the filing wrong. After a decade of ROC work, I can tell you the pattern is always the same: the board resolution exists, the auditor is on the job, and nobody filed ADT-1 until someone notices in March. Don't be that company.

What is ADT-1 filing, exactly?

ADT-1 is the e-form through which a company intimates the Registrar of Companies about the appointment or re-appointment of its statutory auditor under Section 139(1) of the Companies Act, 2013. It covers three situations: a fresh appointment at the AGM, the re-appointment of the existing auditor, and the filling of a casual vacancy. The form is filed with the ROC of the state where your registered office sits, signed digitally by a director and certified by a CA, CS, or CMA in whole-time practice.

Who has to file ADT-1 and by when?

Every company — private limited, public, one-person company — that appoints or re-appoints an auditor must file it. The deadline is fixed by law, not by convenience: within 15 days of the meeting at which the appointment was made. For a September 30 AGM, that's October 15. No extension letters, no grace notes. The ROC portal simply starts counting additional fees from day sixteen.

The penalty structure comes from Section 403: the additional fee is Rs.100 per day of delay. A two-month delay costs you Rs.6,000. A year of neglect costs Rs.36,500. The fee accrues automatically — there is no hearing, no waiver application. It just multiplies.

If your AGM ran late, your ADT-1 deadline runs late with it. The fifteen days are counted from the actual meeting date, not the statutory deadline for the meeting. File it alongside your other annual returns — the AOC-4 financial statements filing and the MGT-7 annual return — and your ROC annual filing season is fully covered.

What documents do you need before filing ADT-1?

Three things must exist before you open the MCA portal. First, the board resolution proposing the appointment and the shareholder resolution passed at the AGM. Second, the auditor's written consent to act as auditor. Third — and this is the one people skip — the auditor's certificate under Section 141 stating that the appointment, if made, would be within the prescribed limits and that the auditor is not disqualified.

The Section 141 certificate matters more than most directors realise. It confirms the auditor hasn't exceeded the limit on the number of audits, has no disqualifying relationships with the company, and meets eligibility conditions. Without it, your appointment is legally incomplete. Get both the consent letter and the certificate in writing, on the auditor's letterhead, before the AGM — not after.

The first auditor: a different clock entirely

Here's where the trickiest concept lives, so let me use an analogy. Think of the first auditor like a newborn's birth certificate. The regular AGM auditor appointment is like a school admission — it follows a fixed annual calendar. But the first auditor has to be appointed within 30 days of the company's incorporation, under Section 139(6), by the board of directors. If the board fails, the members must appoint the auditor within 90 days through an extraordinary general meeting. There is no AGM involved at all. Different birth, different paperwork.

The practical consequence: a newly incorporated company files ADT-1 for its first auditor long before its first AGM ever happens. The fifteen-day rule still applies — fifteen days from the board meeting where the first auditor was appointed. I've seen startups file their first AOC-4 and MGT-7, forget ADT-1 entirely, and discover the gap during due diligence before a funding round. That is an expensive place to discover a missed form.

Casual vacancy: when the auditor resigns mid-year

When an auditor resigns or is removed mid-term, the resulting casual vacancy is filled by the board within 30 days. But unlike a regular AGM appointment, this one must be approved by shareholders within three months of the board's recommendation. And yes — ADT-1 must be filed within fifteen days of the appointment, just like any other. The resignation itself triggers separate obligations on the outgoing auditor, but your filing duty starts from the new appointment.

Common mistakes that cost real money

The classic errors repeat every filing season. Appointing an auditor without collecting the Section 141 certificate. Assuming the auditor's firm will "handle the ROC part" — auditors do the audit, the company's filing is the company's job. Filing ADT-1 with the wrong auditor details, then filing a correction that resets nothing. And the most expensive one: treating ADT-1 as optional because the auditor is already working. The audit engagement letter is a private contract. ADT-1 is the statutory intimation. One does not replace the other.

Also check the auditor's firm registration number and membership number carefully on the form. A transposed digit in the FRN is the kind of error that surfaces during a bank loan verification or an investor's legal due diligence — always at the worst possible moment.

Get it done this week

If your AGM was in September, your ADT-1 is due by October 15. That's days away, not months. Pull the board resolution, the auditor's consent, and the Section 141 certificate, and file. The fifteen-day window is short on purpose — the law wants the ROC's records current while the appointment is fresh.

Handling the full annual compliance calendar — ADT-1, AOC-4, and MGT-7 — is exactly what our ROC annual filing service exists for. And if you're starting from the auditor appointment itself, see our dedicated ADT-1 filing page. File on time. Every year. No drama.