Wild storms hit the ACT on January 21 and damaged approximately 2,300 Telstra services.

It was the third thunderstorm to cause major power outages over the past two months.

Approximately 3,800 Telstra services were affected during a wild storm that ran from December 3 and 4.

Thunderstorms on January 10 also caused significant outages in the ACT.

A Telstra spokesman said the latest thunderstorm "severely impacted" services and this had contributed to an existing backlog of repairs.

There are currently around 600 phone and internet faults waiting to be fixed in the ACT and surrounding districts.

Repairs for services following the first two storms were delayed for up to 10 days last month.

Telstra had expected to return to normal service operations by February before the third storm hit on January 21.

They now estimate service operations will resume on March 1 but warn residents repair delays may continue into the next month.

The Telstra spokesman apologised for the continued delays.

"Our team in Canberra is working hard to fix all outstanding faults and we apologise to our customers who are inconvenienced by these delays," he said.

Telstra said services may not be fixed within its standard repair period of three days due to the high volume of faults.

The company has received an exemption from compliance with time frames and performance standards owing to the exceptional weather circumstances.

Telstra services encompassed in the exemption area include all suburbs and towns bounded by the districts of Nerriga, Braidwood, Jerangle, Bunyan, Batlow, Brindabella and Murrumbateman.

The ACT has had an unprecedented amount of rain this year, reaching its average January rainfall by the 11th day of the month.