Last week, the vaccination program broke the record for most doses given in a single week after over 340,000 jabs were administered.
The HSE's national lead on vaccine rollout, Damien McCallion, said that based on the current supply, people in their 20s should be fully vaccinated by the end of September.
Speaking on RTE Radio One this morning, Mr McCallion said that around another 300,000 people will get jabbed in each of the next three weeks.
Two of the largest deliveries of the Pfizer vaccine estimated to be around 318,000 doses, is set to arrive in the state in the next two weeks.
Pfizer will be the main vaccine given to people in their 20s. There will also be a focus on using the Moderna vaccine as the two become the mainstays of the vaccine program.
The vaccine portal for people in their 30s opened last week with people aged 38 able to register today. People in their 30s will get their first vaccine through June and July and the second in August.
People in their 20's will get their first jab in August and their second dose before the end of September.
As it stands, around 66% of the population have been given one dose and 35% both.
Due to the cyber attack on the HSE in the previous weeks, the vaccine data has not been updated. However, Mr McCallion expects this data to be fully restored by the end of the week.
Getting people fully vaccinated has become even more important with the Delta variant much more transmissible.
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