BT was the most complained about major broadband provider in the final quarter of 2013.
This is according to the latest figures from Ofcom, which show the company received 0.32 complaints for every 1,000 customers.
The telecoms watchdog said these customer grievances were mainly caused by service faults and problems with the way complaints were handled.
EE was the next most complained about provider, with 0.29 unhappy customers for every 1,000. Meanwhile, TalkTalk had 0.21 complaints for each 1,000 user.
The industry average for the five major providers, which also includes Sky and Virgin Media, was 0.29 grievances per 1,000 customers. Virgin attracted the least complaints with just 0.07 for each 1,000 users.
Ofcom's figures follow research from Which? that revealed 63 per cent of people experience problems with their broadband.