Frontier Communications, which provides internet service for rural and suburban areas in California, Florida, Connecticut, and 23 other states, is telling customers services have been restored.
The company replied to tweets from customers, confirming that service has continued.
According to downdetector.com, Dallas, Las Vegas, Anaheim, Tampa, Orlando, Indianapolis, Los Angeles, Riverside and Chicago were the areas most affected.
The telecoms sector has seen a huge increase in demand during the COVID-19 crisis. With lockdown measures keeping people in their homes, digital infrastructure became increasingly essential as people began to move their lives online.
The increase in the numbers of people working, learning and socializing from home has led to a change in customer attitudes with more customers valuing the reliability of their connection over speed.