The US Federal Communications Commission (FCC) has voted to relax rules around so-called net neutrality.
The rules prevented internet service providers (ISPs) from charging customers extra for access to certain sites or services.
Without the regulation, ISPs can charge consumers for access to "bundles" of internet usage, which will give them a faster connection to whichever sites they visit most, whether that's social media or streaming services.
Tech companies like Facebook and Google could also be charged extra by ISPs to prioritise them, while providers could even block sites which compete with one of its own services.
Many tech firms have already voiced concern over the change.
Streaming service Netflix criticised the move, though it has previously told shareholders it had enough popularity among consumers to dodge extra charges from ISPs.
Twitter said the move will hamper "innovation and free expression".
COO Sheryl Sandberg wrote on Facebook that the company was prepared to work with Congress to resolve the issue.
Today’s decision from the Federal Communications Commission to end net neutrality is disappointing and harmful. An open internet is critical for new ideas and economic opportunity – and internet providers shouldn't be able to decide what people can see online or charge more for certain websites.
Although AT&T could take the opportunity to charge online services and customers more under the deregulation, vice president of external affairs Bob Quinn insisted "the internet will continue to work tomorrow just as it always has".
We do not block websites, nor censor online content, nor throttle or degrade traffic based on the content, nor unfairly discriminate in our treatment of internet traffic.
He added that the company supported a legislative solution.
Vimeo channelled Jeremy Corbyn, saying the policy benefited the few, rather than the many.
Chief executive Steve Huffman posted a statement on the website, saying the decision was disappointing but that the fight for net neutrality would continue.
He said while it was unclear what will happen next, one thing was certain: "Reddit will continue to be involved in this issue in the way that we know best: seeking out every opportunity to amplify your voices and share them with those who have the power to make a difference."