Over 2,000 homes in the Glenties and Ardara areas were without power on Thursday night.
The ESB confirmed that a big outage affected 2,043 customers.
The fault was first reported at around 10.45pm.
By 11.10pm, power was restored to the majority of premises.
However, there were still 124 customers without supply. ESB repair crews are working to repair the fault and say full power should be restored by 2.15am.
The ESB apologised to those affected.
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