Anyone eligible for a Covid-19 booster vaccine can now book an appointment online.
The HSE opened an online booking portal on Tuesday after long queues were reported at walk-in centres across Ireland.
The change comes amid concern about the Omicron variant, which is now estimated to make up more than half of all cases in Ireland.
There is expected to be huge demand as people rush to get their third shot ahead of Christmas.
Here’s all you need to know about booking a booster vaccine online
People can now schedule their own appointment at a small number of centres. They are Croke Park in Dublin, The National Show Centre in Swords, Scoil Carmel in Limerick and Astra Active Centre in Wexford.
Walk-in clinics will continue to operate in over 30 locations across the country in addition to the new self-scheduled centres.
It is being rolled out for anyone aged over 40, pregnant women who are aged over 30, healthcare workers, people with underlying conditions and anyone living in nursing homes or long-term healthcare facilities.
Those eligible will need to wait at least three months after their initial vaccine course before getting a booster.
The clinics will use the Moderna vaccine only.
Online booking can be done on the HSE website and people need to bring photo ID that shows their date of birth to their appointment.
Health Minister Stephen Donnelly has said people will be fully protected seven days after getting their booster.
It comes after a change to the vaccination programme concerning the length of time people need to wait between booster doses.
The gap has been reduced from six months to three for anyone who has recovered from Covid-19.
Minister Donnelly welcomed the news and urged people not to wait until after Christmas to get their jab.
“The emergence of Omicron has prompted this amendment, specifically the significant concerns we have about the risk of re-infection which is estimated to be approximately five-fold higher with Omicron compared to the Delta strain.
"Christmas week is an important time for many people as we look forward to seeing family and friends and taking a break at the end of a challenging year. This year, it is important that we take all the measures we can to break the chains of transmission from Covid-19.
“Each of us can take actions this week to protect ourselves and our loved ones, even if this means rethinking plans for the Christmas period, especially if you are not yet boosted or vaccinated.
"Please continue to come forward for your booster dose. Do not wait until after Christmas," he said.
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