About 230 homes in West Auckland are without power after a tree fell on a line in Titirangi about 4pm.
Vector spokeswoman Sandy Hodge said the line is down in Konini Rd and crews are working to isolate the broken line and back-feed the electricity through other lines.
Despite the fact it was just one line, for safety reasons they have to cut power to a larger area.
She didn't know when it would be restored but the Vector website is estimating it to be repaired by 7pm.
There are also minor other minor outages in Piha, Kumeu, Muriwai, Epsom and Te Atatu.
A map showing where the outages are can be found here.