RTS offices fall under the responsibility of the Luxembourg Inland Revenue (Administration des contributions directes – ACD) and are responsible for:

• calculating annual adjustments;
• issuing and updating withholding tax cards (tax cards);
• recording tax reductions on tax cards, or updating tax cards for the current year;
• verifying taxes withheld on wages, salaries and pensions;
• monitoring and managing the receipt of tax cards from employers and pension funds.

There are 5 RTS offices for Luxembourg residents and 1 RTS office for non-residents.