Some 240,000 men, women and children could benefit from radical reform of the tax credit system, campaigners have said.
Dr Sean Healy, of Social Justice Ireland, said offering the working poor cash if they do not earn enough to claim on credits would only cost 140 million euro.
Government forecasts had said it would be up to three billion euro.
Dr Healy said almost 113,300 low income workers would directly benefit from a refund system and would see their disposable income increase as a result of the proposal. "It almost could be introduced with the stroke of a pen. The structures are already in place," he said.
Dr Healy urged the Government to adopt the refund system which would see workers given money directly from the Revenue if their annual salary is too low for them to claim for some tax credits.
He said: "At the end of the year, whoever wanted to get refundable tax credits could apply and would receive them. It could be done online through the Revenue Online Service or by somebody writing."
Social Justice Ireland claimed the research, carried out by academics from Trinity College last year, showed how Ireland's tax system could be made fairer, address part of the working poor problem and improve the living standards of a substantial number of people.
An example showed a single person earning less than 18,300 euro could be in line for a cash payout as they are not earning enough to claim all tax credits.
"The impact would be quite substantial even though the payment would be 800-1,000 euro, that's a huge amount and that makes a big difference," Dr Healy said.
Dr Healy is to detail his figures at a submission to the Oireachtas Joint Committee on Social Protection. A meeting is also planned with the top officials in the Department of Finance in coming weeks.