Up to 719 premises in the Belmullet are experiencing a loss of power supply this afternoon.
The outage occurred just before 2 o’clock due to a fault in the system, according to the ESB powercheck app.
ESB crews are currently working to repair the fault and say they will restore power as quickly as possible.
It is estimated that the power supply will be restored by 4 o'clock.
They have apologized to customers affected for the loss of supply.