Union deduction from your salary in Brazil: can you refuse the assistance contribution?

*A union can charge the assistance contribution (contribuição assistencial) to all workers in the category, including non-members, when it is provided for in a collective agreement — as long as the right to opt out (direito de oposição) is guaranteed (STF, Theme 935 — the STF is the Federal Supreme Court). In 2025, the STF added limits: the charge cannot be retroactive, opting out must be effective and free of obstacles, and the amount must be reasonable.* Do not confuse it with the old mandatory union contribution, which stopped being compulsory in 2017.

Quick summary

• Union contribution (the old "union tax"): optional since the 2017 Labor Reform; only with prior, express authorization (CLT, arts. 578 and 579 — the CLT is Brazil's Consolidated Labor Laws).
• Assistance contribution: provided for in a collective rule to fund bargaining; may reach non-members, with the right to opt out (STF, Theme 935, 2023).
• 2025 adjustment: no retroactive charges; opting out through accessible means equivalent to those for joining; reasonable amount; no interference by employers or third parties.
• Deadline and form for opting out: set in the collective rule; the TST (Superior Labor Court) is still discussing uniform criteria.
• Employer: cannot encourage or discourage opting out.

The three contributions side by side

• Union dues — Who pays: members only · Basis: the union's bylaws
• Union contribution — Who pays: only those who expressly authorize it · Basis: CLT, arts. 578 and 579
• Assistance contribution — Who pays: the whole category, except those who opt out · Basis: collective agreement; STF, Theme 935

Why the issue is controversial

From 2017 to 2023, the prevailing view was that non-members could not be charged. In 2023, the STF changed its position and allowed the charge with a right to opt out. Unions argue that everyone benefits from negotiated raises; critics point to short deadlines, queues and in-person requirements for opting out. That is why, in 2025, the STF stressed that opting out must be effective and free of pressure.

How to opt out

1. Read your category's collective agreement: deadline, form and address for opting out.
2. Opt out in writing, through the channel provided (email, form, letter), and keep the receipt.
3. Give a copy to HR, if the rule requires it, so the deduction does not appear on payroll.
4. Check the following month's payslip.
5. If there is an improper deduction, ask the union and the employer in writing for a refund; if not resolved, contact the Ministry of Labor or the Labor Court.

Frequently asked questions

Am I required to pay the union?

The union contribution, no, unless you authorize it. The assistance contribution may be deducted if provided for in the collective rule and you do not opt out within the valid deadline and form.

Can the union require me to opt out in person?

The STF ruled that opting out must be possible through accessible means equivalent to those for joining, without obstacles. Disproportionate requirements may be challenged.

Do those who opt out lose the collective agreement's raise?

No. The collective agreement applies to the whole category.

Read more in this series

• CLT worker rights: complete guide
• Late wages: payment deadline and what to do
• Reporting labor violations: Ministry of Labor or MPT? How to do it
• How to find a labor lawyer
• Index: complete guide to labor rights