The deal will make the website more valuable than Time Warner, Yahoo and eBay.
Goldman Sachs is said to have invested £289m in the site while Russian investment firm Digital Sky Technologies invested £32m, according to sources close to the transaction.
Facebook is now the largest online social network with around over 500 million users worldwide.
Facebook topped Google as the most visited site in the US last year, with 8.9% of all US visits between January and November compared to Google’s 7.2% of all visits, according to online measurement service Experian Hitwise.
It is thought the investment could place pressure on Facebook to go public, as according to Security and Exchange Commission regulations a company is required to publish certain financial details if it has more than 499 shareholders. Goldman Sachs counts as one investor but will raise money from several clients.