A number of vaccination centres again reached full capacity on Saturday, amid high demand for booster doses.
Walk-in appointments are available at a number of centres across the country this weekend.
However, UCD vaccine centre had reached full capacity by 11:25am this morning and could not accept any further walk-ins.
Other centres such as the National Show Centre in Swords and Clonmel Park Hotel had reached capacity by mid-afternoon, with the latter having reported queue times of over two hours earlier in the day.
The HSE has been offering live updates on queuing times at other centres, with queues of over an hour in Ennis, Greystones, Waterford and more.
A number of centres will be offering walk-in appointments again tomorrow, with full details on the HSE website.
Currently, anyone over 50 is eligible for a booster vaccine - either five months after their second dose, or three months after a single-dose Janssen jab.
It comes after early data indicated that a third dose of a vaccine offers strong protection against the newly-identified Omicron strain of the virus.
Officials including the Taoiseach and Chief Medical Officer have urged anyone eligible for a booster shot to get it as soon as possible, rather than waiting until after Christmas.
Meanwhile, 4,0004 new cases of COVID-19 were reported in Ireland today.
