Unemployment could end up exceeding 390,000 when the pandemic ends - a higher rate than at the peak of the last recession, according to the Social Justice Ireland research body.
Its latest Employment Monitor also shows that over a fifth of people whose jobs have been impacted by Covid-19 do not expect to return to their pre-pandemic job.
Social Justice Ireland warns of a looming crisis of youth unemployment, and calls for an extensive package of measures to support those experiencing joblessness.
According to the body, CSO data suggests the post-pandemic unemployment rate could top 16.1% - the highest since 1986.
The pandemic has impacted the jobs of almost 1.25 million people.
Of those, 21% do not expect to return to their previous jobs.
Of those voicing those fears, almost half are under 34 - potentially heralding a "major explosion" in youth unemployment which was already under way before the pandemic.
The unemployment rate in Dublin could soar to 21% - up 350% - with joblessness doubling in other regions.
Social Justice Ireland calls for an extensive - as yet uncosted - package of investment in training, housing, schools, broadband and other supports - particularly in rural areas - along with tax reform to assist the lower paid and those in vulnerable jobs.
The body's CEO, Dr Sean Healy, noted that emigration is no longer available to assist in reducing joblessness, and warned of the danger of a rise in long term unemployment.