Renua has proposed a flat tax rate of 23% on earners as part of its pre-budget submission.
Party leader Lucinda Creighton said the plan could be introduced over a three-year period.
Renua has also proposed a system of graduated payments, with the maximum payment of €2,500 provided to those on welfare and the minimum wage.
The payments would decrease as the tax payer’s income rose.
Nobody earning over €70,000 would receive a graduated payment.
The majority of tax payers would benefit under the tax plans, but those on minimum wage would be marginally down. However, Renua says their income could rise if overtime is done.
Tax take would be down €3.5bn on current level under the party’s plan.
However, Renua maintains that a shrinking of the black market would increase spending and VAT would then erode the difference.
The party also wants to abolish the TV licence, and to replace motor tax with a levy on fuel.