Consumers in Delhi registered the maximum number of complaints with the National Consumer Helpline (NCH) during the previous month.
In all, NCH received 4,099 complaints from across the country, as much as 14.06 per cent of which were against telecom companies.
With 1,545 complaints, Delhi was on top -- accounting for 37.69 per cent of the total calls -- followed by Uttar Pradesh, Maharashtra, Rajasthan and Haryana, a statement by the Consumer Affairs Ministry said.
However, only 180 complaints were resolved, it added.
Consumers in Uttar Pradesh made 452 calls to the helpline in May, followed by Maharashtra and Rajasthan at 374 and 327 respectively.
Apart from telecom, the NCH also received complaints pertaining to the pharmaceutical, banking and insurance sectors, public distribution system (PDS) and LPG connections.
Consumers from across the country can avail of telephonic counselling through the toll-free NCH number.
The helpline (1800-11-4000), in operation since March 15, 2005, helps resolve problems faced by consumers.