Vaccination of everybody aged over 35 should get underway in June, the Department of Health says.
The vaccination of 25-34 year-olds will then be underway in July.
Officials say the dates - which cover first doses rather than full vaccination - are subject to vaccine supply.
The dates were also shared by Fine Gael:
Based on current information, here is a guide to the #Covid19 vaccination rollout timeline over the next three months.
Thank you to all our fantastic frontline workers who are helping to make this happen. pic.twitter.com/uDm67SWpgE— Fine Gael (@FineGael) April 30, 2021
The timeline comes despite health officials still working to finalise the latest revision of the vaccine rollout plan.
Officials are set to continue working through the weekend, taking into account recent NIAC recommendations around the use of the AstraZeneca and Johnson & Johnson jabs.
HSE CEO Paul Reid yesterday said he expected the vaccination of over-50s to get underway in the 'next two to three weeks'.
Over 50s will be able to register for a vaccine appointment from next week, starting with 59-year-olds.
The Government has said it's still aiming for their target of 82% of all adults being offered a COVID-19 vaccine by the end of June.
Meanwhile, Pfizer and BioNTech have asked European regulators to approve the use of their vaccine in 12-15 year-olds.
No vaccines being used in the EU are approved for use in people under 16.
However, trials by Pfizer showed their jab has a very high rate of efficacy in teenagers.
Some experts believe vaccinating children will be necessary to achieve herd immunity against COVID-19, but a recent study in Israel suggested transmission rates in the community dropped dramatically without children being vaccinated.