Why the backlog is fixable, not a dead end
An unfiled year is not a door that closes forever. The law gives you defined ways back in, and which one applies depends only on how old the year is and whether you owe tax or are owed a refund.
For a non-resident, most backlog years fall into one of two camps. A year where tax was over-deducted — the bank withheld 30% plus cess on your NRO interest under Section 195, or a tenant deducted on gross rent — is usually a refund year: file it and money comes back. A year where a flat or a parcel of shares was sold and the gain wasn't fully covered by TDS may be a tax-due year: file it and a balance, with interest, is paid.
The clean-up sorts each unfiled year into the right route and works through them in order. It is methodical rather than dramatic, and a few unfiled years is a situation a CA handles regularly — the value is in doing it before the refund windows close and before a mismatch query forces the timing.
The two routes: belated return and Updated Return (ITR-U)
Two different filing routes cover the recent and the older years, and they don't overlap.
The most recent unfiled year can usually still go in as a belated return under Section 139(4) — generally up to 31 December of the assessment year — with a late fee and interest on any tax due. A belated return is a full, normal return: it can carry a refund, which matters when the year is over-deducted NRO TDS.
Once the belated window for a year has passed, that year moves to the Updated Return route — ITR-U, under Section 139(8A). The window for an ITR-U was extended by the Finance Act 2025 to four years from the end of the relevant assessment year (up from two). So as the years roll, the most recent one or two are belated-eligible and the ones behind them are ITR-U territory.
| Route | Which year it covers | Can it carry a refund? |
|---|---|---|
| Belated (Section 139(4)) | The most recent unfiled year | Yes |
| Updated / ITR-U (Section 139(8A)) | Older years, up to 4 years back | No |
| Condonation (Section 119(2)(b)) | An old refund ITR-U can't claim | Yes — that's its purpose |
The practical first step is simply mapping each unfiled year to the right row before a single return is drafted.
The ITR-U cost and its one big limitation
An Updated Return is deliberately not free of cost, and it has one restriction that shapes the whole clean-up.
The cost is an additional tax under Section 140B, charged on the tax-and-interest payable, and it climbs the longer you wait: broadly 25% if the ITR-U is filed within twelve months of the end of the assessment year, 50% within twenty-four months, 60% within thirty-six months, and 70% within forty-eight months. The lesson built into that ladder is that an older year filed sooner costs less additional tax than the same year filed a season later — there is a real saving in not waiting.
The limitation is the one that catches people out: an ITR-U cannot be used to claim a refund, to increase a refund, or to report a loss. It is a route for declaring income that should have been taxed and paying what's due on it, not for getting money back. So a genuinely refund-due old year — say a year where the only Indian income was NRO interest taxed at 30% — cannot be recovered through ITR-U at all. That is exactly the gap the next route fills.
Recovering old refunds through condonation
Where an old year is refund-due but too old to file belated and barred from ITR-U because ITR-U can't carry a refund, the refund isn't simply lost. It is claimed through a condonation of delay application under Section 119(2)(b).
This is a request to the tax authority for permission to file a late return specifically to claim the refund (or to carry forward a loss). Under the current CBDT guidelines, such an application can generally be made up to five years from the end of the assessment year the refund relates to, and once permission is granted the return is filed and the refund processed. The application explains the genuine reason the year went unfiled — being abroad, unaware of the over-deduction, no tax otherwise due — and is supported by the figures showing the refund was real.
This is why an honest multi-year clean-up often runs on two parallel tracks at once: tax-due old years go in as ITR-U with their additional tax, while refund-due old years go through condonation to actually get the money back. Sorting which year is which, before filing anything, is the part that decides how much you recover.
A worked example: Sandeep's six unfiled years
Sandeep moved to Toronto and last filed an Indian return six years ago. Since then his NRO fixed deposits earned interest that the bank taxed at 30% plus cess every year under Section 195, he rented out a Pune flat with the tenant deducting on the rent, and in one of those years he sold an old parcel of listed shares at a gain.
Working back from the current year, the picture sorts cleanly. The most recent year is still inside the belated window, so it goes in as a Section 139(4) return — and because his only income that year was over-deducted NRO interest and rent, it carries a refund. The next few years back fall inside the four-year ITR-U window. The share-sale year turns out to be tax-due once the gain is computed, so it is filed as an ITR-U, paying the balance plus the Section 140B additional tax — and because that year sits in the earlier part of the ladder, the additional tax is at a lower tier than it would be if he waited another year.
The oldest two years are refund years — pure NRO interest, taxed well above his real liability, nothing owed. ITR-U can't recover those because it can't carry a refund, so they go through Section 119(2)(b) condonation, with an application setting out why they went unfiled and the figures showing the over-deducted TDS. Filed across the three routes in the right order, Sandeep ends up fully current, has paid the one genuine balance he owed, and recovers refunds from years he'd assumed were gone. Done piecemeal — or left another year — the refund windows would have started closing and the additional tax on the tax-due year would have ticked up a tier.