The Duke and Duchess of Sussex's Instagram account amassed more than one million followers in record-breaking time, Guinness World Records has said.
The couple's official account took five hours and 45 minutes to reach the milestone after its launch on Tuesday.
The previous record was held by Korean pop star Kang Daniel, who hit the mark in 11 hours and 36 minutes in January.
The official account, sussexroyal, will be used for "important announcements" and to share work that "drives" them.
Congratulations to the Duke and Duchess of Sussex, Prince Harry and Meghan Markle, whose new @instagram account sussexroyal reached one million followers in less than 6 hours https://t.co/manigokiw5 🎉— GuinnessWorldRecords (@GWR) April 3, 2019
Kang Daniel launched his Instagram on New Year's Day, knocking Pope Francis's record of 12 hours out of the record books.
The Vatican's Instagram account, Franciscus, began in 2016.
David Beckham clawed his way to a million followers after 25 hours in 2015.
Harry and Meghan's new account splits their Instagram feed from the one they shared with the Duke and Duchess of Cambridge, kensingtonroyal, which has 7.2 million followers.
The first image shared was a navy background with the couple's royal cypher - the entwined initials H and M below a coronet - in white.
A further nine pictures of them were shared, showing the duke and duchess on official visits around the world and of causes important to them.
In their first post, Harry and Meghan said: "Welcome to our official Instagram; we look forward to sharing the work that drives us, the causes we support, important announcements, and the opportunity to shine a light on key issues. We thank you for your support, and welcome you to @sussexroyal."
Harry and Meghan are expecting a baby this month and are due to move to Frogmore Cottage, in the grounds of Windsor Castle, in the coming days.
Last month, the Royal Family published social media guidelines for the public, vowing to block users who leave offensive or abusive comments on official channels.
The move followed reports of a surge in abuse aimed at the Duchesses of Cambridge and Sussex.
Meghan closed down her own personal social media accounts last year, before marrying Harry.
In December 2017, shortly after her engagement, she had 1.9 million people following her posts on Instagram, and more than 350,000 Twitter followers. Her Facebook page had almost 800,000 likes.
The Royal Family set up its official Instagram account, theRoyalFamily, in 2013 and now has five million followers.
The Queen personally posted a photo on the account for the first time last month.