Every UDIN rule that matters for the FY 2026-27 season, on one page – with a free Excel register that enforces them for you. The two numbers every practitioner now lives by: 60 days to generate the UDIN from the date of signing, and 60 tax audits per member per financial year from 1 April 2026. The register below counts down the first and counts up the second – partner-wise, with the exclusions handled correctly.
A protected, formula-driven workbook: log each document on signing day, watch the 60-day countdown with OVERDUE flags, and track each partner’s 44AB(a)/(b) count against the ceiling – with 44AB(c)-(e) audits and out-of-year entries excluded automatically. Five sheets: Cover, UDIN Register (200 rows), Tax Audit Cap, Summary dashboard, Rules.
Download the UDIN tracker (.xlsx)
The UDIN rules, verified July 2026
| Rule | Position |
|---|---|
| Generation window | Within 60 days of signing the document (UDIN FAQs, 6th edition, January 2026). Where a regulator prescribes a shorter window for a particular filing, the shorter window governs |
| Revocation | Within 48 hours of generation, with reasons recorded on the portal |
| Income-tax e-filing | Forms uploaded on the e-filing portal need the UDIN updated within 60 days – an un-updated form is treated as invalid |
| The tax audit ceiling | 60 tax audit assignments under section 44AB per member per financial year, effective 1 April 2026 (Council Guidelines 1-CA(7)/234/2025 dated 25 July 2025). The count is per member, aggregated across all firms and capacities – one partner’s unused limit cannot be used by another |
| What counts toward 60 | Only audits under section 44AB(a) and 44AB(b). Excluded: audits under 44AB(c) to (e) (the presumptive opt-out cases), revised tax audit reports (not counted again), and head office plus branches of the same assessee for the same year (counted once) |
| How it is enforced | The UDIN portal blocks generation beyond the ceiling, reckoned by the date of signing (ICAI FAQ, May 2026) – so the sixty-first report cannot get a UDIN at all |
| Scope phase-in | Certificates since 1 February 2019; GST and tax audit reports since 1 April 2019; every other attest function since 1 July 2019 |
| What needs no UDIN | Non-attest documents – engagement letters, management representation letters, quotations and routine correspondence |
| Consequence of default | Failure to generate a UDIN where required is misconduct referable under the Second Schedule to the CA Act; banks, registrars and authorities verify UDINs independently at udin.icai.org |
UDIN – FAQs
What is the time limit for generating a UDIN in 2026?
Sixty days from the date of signing the document, under the current UDIN FAQs (6th edition, January 2026). The window was 15 days in the early years – it has been 60 days for some time now, but where a regulator or authority prescribes a shorter period for a specific filing, that shorter period applies.
Can a UDIN be revoked or corrected?
A UDIN can be revoked within 48 hours of generation, with reasons. Beyond that, there is no editing – if a document is revised, the revised document gets its own UDIN with a reference to the earlier one. Log both in the register; a revised tax audit report does not count again toward the ceiling.
What is the 60 tax audit limit effective 1 April 2026?
Council Guidelines 1-CA(7)/234/2025 (25 July 2025) cap tax audit assignments under section 44AB at 60 per member per financial year, effective 1 April 2026. It is a per-member cap aggregated across every firm and capacity in which the member signs – a firm cannot pool its partners’ limits, and the UDIN portal enforces the cap by signing date.
Which audits are excluded from the 60 limit?
Audits under section 44AB(c) to (e) – the cases that trip into audit only because the assessee opted out of presumptive taxation – do not count. A revised tax audit report is not counted again, and the head office and branches of the same assessee for the same assessment year count as a single assignment.
Does an engagement letter or MRL need a UDIN?
No. UDIN attaches to attest documents – certificates, audit reports, examination reports. Engagement letters, management representation letters and quotations are communications, not attestations, so no UDIN is generated on them.
What happens if the UDIN is generated after 60 days?
The portal does not permit back-dated generation beyond the window, and signing without a valid UDIN where one is required is misconduct referable under the Second Schedule. On the income-tax side, a form whose UDIN is not updated within 60 days of upload is treated as invalid – which can undo an otherwise timely filing.
Who verifies UDINs, and how?
Banks, registrars, tax authorities and other regulators verify UDINs directly at udin.icai.org using the document date and the number – no login needed. That is exactly why a missing or mismatched UDIN surfaces quickly on certificates used for loans, visas or tenders.
Since when has UDIN been mandatory?
In three phases: certificates from 1 February 2019, GST and tax audit reports from 1 April 2019, and all other audit and attest functions from 1 July 2019. Anything signed in an attest capacity today needs one.
How does the free tracker handle all this?
One row per document on signing day. The register computes the 60-day deadline, shows a live countdown, flags OVERDUE items in red and late generation in amber. The Tax Audit Cap sheet counts each partner’s 44AB(a)/(b) audits within your chosen financial year against 60 – excluding 44AB(c)-(e) entries and out-of-year rows automatically – and the Summary sheet gives the season dashboard.
Is the workbook protected? What is editable?
The sheets are protected so the formulas cannot be broken by accident; every input cell is yellow and open – dates, clients, types, partners, UDINs. Row one of the register carries a worked example to overwrite. Nothing you type leaves the file; it is a plain Excel workbook with no macros.
Method notes: rules stated per the UDIN FAQs (6th edition, January 2026), Council Guidelines 1-CA(7)/234/2025 dated 25 July 2025 on the tax audit ceiling, the ICAI FAQ of May 2026 on portal enforcement, and the phase-in notifications of 2019 – as they stand in July 2026. All wording is original; nothing is reproduced from ICAI publications. The workbook is formula-verified (39-check battery) and protected without macros; review your own facts before relying on any flag it raises. Reviewed by a practising CA; updated July 2026.