Mr Biden's team will now be able to tweet from the various institutional accounts, which have been controlled by the Trump administration for the last four years.
In addition to the president's @POTUS account, Twitter also organised the transition of other official accounts, including @WhiteHouse, @VP, @FLOTUS and @PressSec.
This year will also see the creation of a new account – @SecondGentleman – which will be run on behalf of vice president Kamala Harris's husband Doug Emhoff.
All of the tweets that were posted by Mr Trump’s team will be transferred to the National Archives and Records Administration (NARA). They will live on as renamed accounts that will be looked after by NARA, meaning that the accounts, their history and posts will be permanently and publicly accessible.
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The same process happened at the end of Barack Obama’s presidency, in 2017.
The new accounts will actually be renamed versions of existing accounts. The POTUS account is the one previously known as @PresElectBiden, for instance, and the White House account is the one that was previously run by the transition team.
All of their tweets and followers will transfer between the two. That will mean that the @POTUS account does not inherit the 33 million followers that were on the version of the account run by Mr Trump and his team.
But Twitter said that people who already followed institutional accounts – or who “follow relevant Biden or Harris Twitter accounts” – will receive in-app alerts and prompts that will tell them about the tweets being archived and ask them if they want to follow the accounts representing the new administration.
Twitter’s process for handing over the accounts came amid ongoing arguments about Donald Trump’s now-suspended personal account, and the decision to remove him from the platform. As Mr Biden was being sworn in as president, a Twitter representative admitted that the company could have handled the removal of Mr Trump’s account better.