New Delhi, Mar 9 (PTI) The Income Tax Department has detected under-reporting of sales worth Rs 408 crore after it conducted a nationwide survey of restaurants on charges of tax evasion, the CBDT said on Monday.

After visiting business premises of restaurants on Sunday, the taxman is now sending emails and messages to 63,000 such outlets, "requesting" them to update their income tax returns (ITRs) by March 31, the Central Board of Direct Taxes (CBDT) said in a statement.

The action is part of the NUDGE -- Non-Intrusive Usage of Data to Guide and Enable -- campaign.

"A nationwide survey was conducted on 62 restaurants across 46 cities in 22 states. On a preliminary basis, the exercise revealed suppression of sales amounting to around Rs 408 crore," the CBDT said.

The cities where the survey was undertaken include Delhi, Shimla, Murthal (Harayana), Gurugram, Guwahati, Mumbai, Chennai, Kolkata, Siliguri, Godhra, Ahmedabad, Bengaluru, Kollam, Kochi, Madurai, Coimbatore, Raipur, Bhopal, Indore, Ajmer, Jaipur, Chandigarh, Ludhiana, Koderma, Patna, Cuttack and Puri, among others, according to I-T department officials.

The statement said that a probe into these findings is underway.

The CBDT said the investigation began after the taxman initiated a probe in November 2025 covering the food and beverage sector.

"During the exercise, it was found that several restaurants were engaged in deletion of bulk bills and other modifications to suppress the actual sales," it said.

Advanced analytics of transactional data from about 1.77 lakh restaurants was carried out through AI tools. This data was compared with the turnover reported by these outlets, leading to the identification of "large-scale" under-reporting of income, the CBDT said.

In some cases, the recorded sales were not fully reflected in financial accounts or tax filings, and certain transactions were excluded from reported sales, it said.

Officials told PTI that the probe began after the department's investigation wing in Hyderabad recently surveyed the premises of a local company that creates restaurant billing software.

It was discovered that certain hotels and restaurants were allegedly manipulating the software to under-report their income, they said. PTI NES DIV DIV

Under-reporting of sales detected - data-driven inquiry prompts compliance notices for restaurants to update tax filings. A data-driven exercise found under-reporting of sales in the restaurant sector through AI analytics comparing transactional data with reported turnover, revealing deletion and modification of bills and omission of transactions. The tax authority has opened investigations and, under the NUDGE campaign, is directing identified outlets to update their income tax returns by a compliance deadline while probes into billing-software manipulation and sampled premises continue.