People Before Profit says the government could raise an extra 3.5 billion euro by clamping down on corporate tax avoidance.
It's included the measure as part of its pre-Budget submission published this afternoon.
The group says it hasn't sent its proposals to be costed by the Department of Finance, because it refuses to cost its proposals for a wealth tax.
But Richard Boyd Barrett TD says it's easy to figure out how much companies should be paying:
