President Obama on Thursday signed an emergency declaration making Philadelphia and its suburbs disaster areas.
The move makes state and federal aid available to Bucks, Chester, Delaware, Montgomery and Philadelphia counties.
FEMA help will be coming first, NBC reported, in the form of generators for hospitals and nursing homes.
More than 400,000 people still were without power Thursday night, as temperatures dipped down into the teens.
In a notice to customers on its website, PECO wrote that it hoped to restore power to a majority of its customers by Friday night, but warned that many will be without power through Sunday.
PECO is not letting customers know which restoration group they are in. Calling the company's customer service number yields an automated message acknowledging the power outage, but telling customers that no timeline for restoration is available.
PECO has brought in outside contractors, it said, and more than 3,500 people are working to restore service.
The ice storm was the second-largest service disruption in PECO history, the company said, and was the most people ever without power during a winter storm.