Some 360,000 pensioners and medical card holders will face a hike in their Universal Social Charge from the start of next year.
The increase will come about as a result of a special low rate of 4% coming to an end, and being replaced by a 7% rate.
The Irish Independent reports that those affected will be hit by as much as €700 a year.
At the same time, high-earning self-employed people will also see a drop in their 10% USC rate to 7% resulting in savings.