Throttling

What It Means

Throttling is the intentional reduction of internet service speed by an ISP, applied either to specific traffic types, specific services, or to a subscriber's entire connection after a data threshold is exceeded. Forms of throttling include: activity-based throttling (slowing peer-to-peer file sharing or BitTorrent traffic, once widespread but now rare), service-specific throttling (slowing Netflix or YouTube while leaving other traffic unaffected), deprioritization (T-Mobile Home Internet subscribers consuming over 1.2 TB per month may be deprioritized during network congestion), and data cap throttling (Viasat and HughesNet satellite subscribers who exceed monthly caps are throttled from 25 to 100 Mbps down to 1 to 3 Mbps for the rest of the billing cycle). Throttling is often invisible to users, a Netflix stream may silently downshift from 4K to 720p without any error message. The FCC's 2015 net neutrality rules prohibited ISPs from throttling or blocking legal content, and the 2024 restoration of Title II reclassification reimposes these rules. Several states (California, New York, Washington, Oregon, Maine) have state-level net neutrality laws that prohibit throttling independent of federal rules. A VPN can sometimes mask activity-based throttling because it encrypts traffic so the ISP cannot identify what the subscriber is doing, though VPNs do not bypass deprioritization or data cap throttling. If your Broadband Grade speed test shows fast speeds but specific services (Netflix, YouTube, Zoom) feel slow, activity-based throttling or CDN routing issues may be the cause. A cross-check with Fast.com (Netflix's own test) can confirm whether Netflix-specific throttling is occurring.

Frequently Asked Questions