Many Vectren customers were without power late Tuesday night into Wednesday morning in Evansville and Newburgh.
As of 5:35 a.m., Vectren has restored electricity to all of those customers.
Around midnight, there were about 1,300 outages.
The official cause remains under investigation, but spokesperson Mike Roeder says it is most likely an equipment failure.
Roeder says it took a several hours to fix because workers had trouble isolating the circuit that was at fault.
The last group of customers to see the lights come on were in the Keystone Subdivision by the airport.
You can keep track of outages anytime on Vectren's website.