Lateral flow testing kits have run out on the government's website, a message on gov.uk says.
People that try to order testing via the official website are currently receiving a message that says they are unavailable.
The Government website on Monday said "there are no more home tests available".
It advised people to "try again later" or to book a test site appointment instead.
"Sorry, there are no more home tests available right now," the message reads.
"Try again later.
"Or, you can go back and try to book a test site appointment instead."
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This comes after the Welsh Government announced on Friday that they "strongly advised" people to take a lateral flow test before going out or going to meet friends and family.
The First Minister of Wales Mark Drakeford said on Friday that the country would remain at alert level zero - meaning all businesses could remain open and there would be no restrictions on meeting people.
Despite worries over the impact of the Omicron variant on Covid rates, no major changes were introduced.
However, the government "strongly advised" people to take a lateral flow test before going out whether to a Christmas party, Christmas shopping, visiting friends or family, going to any crowded or busy place as well as before travelling.
People have taken to social media in response to the home testing kits being unavailable on the UK Government website.
One person said on Twitter: "Tried to order a lateral flow test kit and the NHS site says they have no more! What's going on!"
Another one tweeted: "You literally couldn't make this up".
While another person said: "Genius. Announce that people need to have tests but don't ensure that you have anywhere near enough."
However, it appears there are no problems with the availability of PCR home test kits.
WalesOnline have approached the UK and Welsh Government for comments.
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