Orange/EE was the most complained-about major broadband provider in the third quarter, Ofcom figures have revealed.
The telecoms watchdog said the organisation received 0.45 complaints per 1,000 customers, which is more than any other company and double the industry average. Billing and service faults were listed as the main factors that caused users' grievances.
BT received the second highest number of complaints, with 0.41 unhappy customers in every 1,000. Meanwhile, TalkTalk had 0.27 grievances for each 1,000 users.
Sky and Virgin Media were the best performing providers, as their services drew 0.09 and 0.08 complaints per 1,000 customers respectively.
This is the fifth straight quarter in which Orange/EE has been the most complained-about broadband provider. The number of grievances the company received hit a peak in the final quarter of 2012, when it experienced 0.7 complaints for each 1,000 users.
Currently, the industry average stands at 0.22 complaints per 1,000 customers, which is up from 0.18 in the second quarter.
Ofcom also revealed complaints figures for other major telecoms services such as landline and mobile phone and pay TV.
BT was by far the most complained-about for the latter, receiving 0.56 complaints per 1,000 customers compared to the industry average of just 0.06.
T-Mobile was the best performing organisation in the mobile phone market, attracting 0.13 complaints for every 1,000 subscribers. Meanwhile, TalkTalk received the most landline complaints - 0.31 per 1,000 customers.
Claudio Pollack, Ofcom's consumer group director, said the organisation provides this data to help people make informed decisions on which company to use for their telecoms services.
"We also hope this data will incentivise providers as they work to address issues driving complaints and improve their performance," she added.