Terms of Service (ToS), also called Terms of Use or Terms and Conditions, is a legally binding agreement between a website or application operator and its users that establishes the rules, restrictions, and obligations governing the use of the platform. This document functions as a contract of adhesion, meaning the service provider drafts the terms unilaterally and users accept them by accessing or using the service. The enforceability of terms of service depends on how users manifest their consent, with courts distinguishing between clickwrap agreements (where users actively click an accept button) and browsewrap agreements (where terms are posted on the site without requiring active acceptance).

The legal foundation for terms of service enforceability was strengthened by courts in cases such as Specht v. Netscape Communications Corp. (2002), where the Second Circuit held that browsewrap terms are not binding unless the user has actual or constructive notice of the terms. By contrast, clickwrap agreements where users must affirmatively check a box or click a button have been consistently upheld, as established in Feldman v. Google (2007). The FTC Act (15 U.S.C. Section 45) also governs terms of service by prohibiting unfair or deceptive practices, meaning terms that mislead consumers or impose unconscionable conditions may be challenged by the FTC or deemed unenforceable by courts.

Terms of service serve multiple legal functions: they define the scope of the service being provided, limit the operator's liability, establish intellectual property ownership over user-generated content, set rules for acceptable use, comply with regulatory requirements, and provide the legal basis for account termination and dispute resolution. For businesses that collect user data, the terms of service work in conjunction with the privacy policy to create a comprehensive legal framework.

Terms of service are needed by any business that operates a website, mobile application, SaaS platform, or online service accessible to users. E-commerce businesses need terms of service that address product descriptions, pricing accuracy, order acceptance procedures, shipping and return policies, and limitations on liability for product defects, complementing their separate return policy and privacy policy. SaaS companies need terms that define subscription tiers, service level commitments, data ownership, API usage limitations, and the consequences of exceeding usage limits.

Social media platforms, forums, and community websites need terms of service that establish content moderation policies, user-generated content licenses, intellectual property infringement reporting procedures under the DMCA (17 U.S.C. Section 512), and community guidelines with enforcement mechanisms. Mobile application developers must include terms of service that comply with Apple App Store and Google Play Store requirements, address in-app purchase terms, and disclaim liability for third-party integrations.

Marketplace platforms connecting buyers and sellers need terms that clarify the platform's role as an intermediary rather than a party to transactions, establish commission or listing fee structures, and define seller obligations for product quality and regulatory compliance. Free service providers including ad-supported websites, educational platforms, and open-source project sites need terms of service to protect their intellectual property, limit liability for service interruptions, and reserve the right to modify or discontinue the service.

The acceptance mechanism section must describe how users agree to the terms, whether through clickwrap acceptance during account registration, continued use of the service, or a combination. Include the effective date, the process for updating terms (typically by posting revised terms with an updated effective date), and how users will be notified of material changes. Under Meyer v. Uber Technologies (2017), courts have emphasized the importance of clear, conspicuous notice and unambiguous consent mechanisms.

The user conduct and acceptable use policy should define prohibited activities including illegal use, harassment, spam, intellectual property infringement, reverse engineering, data scraping, and attempts to circumvent security measures. For platforms that host user-generated content, include a content license granting the platform the rights needed to display, distribute, and store user content, while specifying whether the user retains ownership. Address DMCA compliance by designating a registered agent for copyright infringement notices and establishing the notice-and-takedown procedure required by 17 U.S.C. Section 512(c). Include COPPA compliance provisions (15 U.S.C. Section 6501) if the service may be accessed by children under 13, specifying the minimum age requirement and parental consent procedures.

Limitation of liability and warranty disclaimer provisions should disclaim warranties of merchantability and fitness for a particular purpose to the maximum extent permitted by applicable law, cap the operator's total liability (typically to the amount paid by the user in the preceding 12 months), and exclude consequential, incidental, and punitive damages. Include an indemnification clause requiring users to defend and hold harmless the operator against claims arising from the user's violation of the terms or applicable law. The dispute resolution section should specify whether disputes are resolved through binding arbitration (referencing the Federal Arbitration Act, 9 U.S.C. Section 1) or litigation, the applicable forum or arbitration organization, and whether class action waivers are included (upheld by the Supreme Court in AT&T Mobility v. Concepcion, 2011). Designate the governing law jurisdiction and include a severability clause.