The USC – Universal Social Charge was introduced in January
2011 – It was supposed to replace the Income Levy and the Health levy.
Many lower paid workers would have previously been exempt from the Income Levy and the Health Levy – but they will now be having USC deductions from payslips.
Also – some workers who didn’t pay Income Tax became liable for USC as soon as they earn €77 a week.
Updated see the current – 2021 USC calculation
See here for USC Income exemptions