The launch of , which used to be published under a subscription model on the website Ireland.com, follows the redesign of The Irish Times print edition in February this year.
The change from a subscription model to a free access model is another major editorial development in the history of the newspaper -- aimed at making it the biggest media site in Ireland.
Online readers will have access to the previous 12 months of The Irish Times free of charge. However, access to the full archive dating back to 1859 will be subscription based.
Geraldine Kennedy, editor of The Irish Times, said: "This newspaper has had a proud and progressive history online.
"In 1994, it was the first newspaper in Ireland or the United Kingdom to establish an online presence, and one of the first 30 newspapers in the world to do so."
As of today, the web address, which The Irish Times used for almost a decade, will be relaunched as Ireland's new homepage, which will be a brand new, free, Irish website.