3 answers
You have every right to question it, but you need to be strategic. What the others said is correct in the fundamentals, but there's an important nuance: even if it's illegal, the reality is you need to document everything before you act. Request in writing (email works) a complete breakdown of every deduction since you started, with dates and reasons. Do it professionally, without direct accusations, like "I need to understand the deductions on my payslip to verify they're correct". Keep that request and the response.
If your employer can't justify the deductions with documentation and your prior consent, then yes, you have a strong position. But before you go to the labor inspectorate (which is what you'd do if it doesn't get resolved), try to resolve it internally while leaving a written record. If they respond with something like "it's for damage at the store" or "for undocumented absences", that's a huge red flag. At that point you already have evidence they're withholding illegally.
The key is that even though it's clearly illegal, proving it requires you to have the paper trail in hand. Once you do, the labor inspectorate acts fast because this is straightforward for them. Some employers count on the employee staying quiet out of fear, so simply asking for documentation in writing sometimes makes them stop.
No, in most jurisdictions that's not legal. Employers can't withhold part of your salary without your explicit written consent, and even then there are limits on what they can legally withhold (generally only taxes, social security, and things you've authorized). What your employer is doing is pretty questionable, and I'd recommend you document everything - dates, amounts, communications - and consult with an employment lawyer or file a complaint with your country's labor authority, because that sounds like a clear violation of your rights.
What you need to do is request a detailed written explanation of those deductions. Your employer is legally obligated to justify every payroll deduction, and if they don't have your signed authorization, they're almost certainly acting outside the law. Keep all your pay stubs where you can see those amounts deducted.
Once you have clear documentation, contact the labor inspection office in your autonomous community or speak with an employment lawyer. Most can give you a free initial consultation, and many take these cases without charging upfront if they see you have a strong case. Illegal wage deductions are pretty serious for employers, so there's usually room to recover what they owe you, plus fines for the company.
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