Total domestic sales were down 2 per cent at 73,448 units as against 74,755 units in the year-ago month, it added.
Domestic passenger vehicle sales were up 6 per cent at 45,878 units as compared with 43,341 units in May last year, Tata Motors said.
Sales of passenger electric vehicles, including international business, were at 5,805 units as against 3,505 units in the same month a year ago, a growth of 66 per cent.
The company said its total commercial vehicle sales stood at 28,989 units last month, down 12 per cent from 32,818 units in May 2022. Similarly, domestic commercial vehicle sales were down 12 per cent at 27,570 units as against 31,414 units in the corresponding month last year.