A recent service tax department survey of air-conditioned restaurants in the city revealed that over 150 air-conditioned restaurants have not registered themselves with the department.
"We surveyed 700 addresses of restaurants located in Mumbai between June 29 and July 6 involving 70 officers.
We found that 40 bars and 115 restaurants have not registered with us," said an official from the department said.
The survey was carried out after air-conditioned restaurants with liquor licences were brought under the ambit of service tax from May 1, 2013.
Service tax officials said that such surveys would be intensified in the coming days to net tax evaders.