Each state has a Public Utility Commission (PUC) that regulates these kinds of things. As a result, the laws governing when we disconnect services varies from state to state.
Generally, accounts that go unpaid are first suspended and then disconnected. Once the bill has been paid in full, suspended accounts can usually be turned back on within 24 hours. Because they require we send someone out to physically turn the service back on, disconnected accounts cost more and take longer to re-activate. Plus, a deposit may be required to get service re-installed.
If you would like specifics, contact us, and we'll answer your questions.