Internet service provider (ISP) is an entity that provides customers or networks with access to the Internet. Common access technologies include fiber, cable, digital subscriber line (DSL), fixed wireless, mobile wireless, satellite, among other technologies. An ISP may also supply services such as email, domain-name resolution, web hosting, security tools, or voice service, but those functions are not necessary to the basic access-provider role. In the United States, ISPs are regulated at the federal level by the Federal Communications Commission (FCC) and at the state level. The largest ISPs in the United States include AT&T Internet Services, CenturyLink, Charter Communications, Comcast High Speed Internet (Xfinity), and Verizon High Speed Internet.
In federal communications regulations, the more precise term "broadband internet access service" means a mass-market retail service by wire or radio that allows users to send data and receive data from all or substantially all Internet endpoints. The definition excludes dial-up access and, for the Federal Communications Commission's broadband-label requirements, generally excludes individually negotiated customized services. Under 47 C.F.R. § 8.1, broadband Internet access providers must disclose specified information about network management, performance, commercial terms, and must display broadband consumer labels for offered plans.
Under the Communications Act, broadband internet access service is currently treated as an "information service," not a Title II "telecommunications service." That classification follows from In re MCP No. 185, 124 F.4th 993 (6th Cir. 2025), in which the Sixth Circuit set aside the FCC's 2024 Title II reclassification and open-internet/net neutrality rules. The principle of “net neutrality” refers to the idea that ISPs should not interfere with the ability of end users or websites to access content on the Internet. Separate transparency and broadband-consumer-label requirements remain in effect under 47 C.F.R. § 8.1.
The term ISP does not automatically include every online platform, website host, cloud provider, or content company. One company may perform several of those roles, but a service that stores or displays online content does not necessarily provide the customer's Internet connection. The distinction matters because federal statutes use broader functional definitions.
For example, 47 U.S.C. § 230 applies to a provider or user of an "interactive computer service," a category that includes Internet-access services but also reaches other systems that give multiple users access to a computer server. Section 230 contains protections concerning third-party content and good-faith content restriction, but it also preserves specified areas of law, including federal criminal law, intellectual-property law, communications-privacy law, and certain sex-trafficking claims or prosecutions.
Copyright law uses another definition. Under 17 U.S.C. § 512, "service provider" has a narrow meaning for the safe harbor covering transmission, routing, and connections, and a broader meaning for the other safe harbors covering online services or network access. Those safe harbors are conditional and apply separately to different functions. Accordingly, "ISP," "broadband internet access service provider," "interactive computer service," and Section 512 "service provider" should not be treated as interchangeable. The applicable definition depends on the statute, regulation, and activity at issue.
For additional information, see the CRS Report on Telecommunications.
[Last reviewed in July of 2026 by the Wex Definitions Team]