EE, Virgin Media and Vodafone have thrown their support behind net neutrality by signing up to the Open Internet Code.
Open Internet Code was launched in 2012 by the Broadband Stakeholder Group (BSG), and commits the three internet service providers (ISPs) to provide full internet access with no data blocked "on the basis of commercial rivalry."
This latest development means that all major ISPs providing fixed and mobile networks in the UK are signed up to the code.
BSG CEO Matthew Evans said: "Unlike some countries, where net neutrality has become a controversial topic for discussion, the UK benefits from a fiercely competitive market and high levels of transparency - which together offer the best assurance of an open internet."
"The code now provides an even stronger and more effective foundation, whilst also allowing for an environment where new business models for internet-based services which benefit consumer choice can thrive."