Netflix, Instagram and Pinterest used Twitter and Facebook to update subscribers after violent storms across the eastern U.S. caused server outages for hours.
Netflix and Pinterest restored service by Saturday afternoon.
Netflix, Pinterest and Instagram are customers of Amazon's Web services division. The unit provides Web services and data storage facilities that are commonly used for "cloud computing."
Amazon spokeswoman Kay Kinton told The Associated Press in an email that the storm cut power to some of the company's operations. Service has been restored for most customers, Kinton said.
Netflix, a video streaming service, said on Twitter that subscribers should reconnect if they still experience problems.
The Friday evening storms knocked out power for millions of people.