Illegal Interview Questions: What's Off-Limits

The line between curiosity and discrimination

You’re in a job interview. The atmosphere is relaxed, the conversation flows well. And then the interviewer asks a question that makes you raise your eyebrows. ‘Are you planning to have children soon?’ Or: ‘Where are your parents originally from?’

Maybe the interviewer meant no harm. But that doesn’t matter. Certain questions are simply not allowed in job interviews. They can lead to discrimination, whether conscious or unconscious. And as a recruiter, they can get you into serious trouble.

This article explains which questions are prohibited, why they’re problematic, and how recruiters can formulate better alternatives. Because the goal isn’t to learn less about your candidates. The goal is to ask the right things.

Why certain questions are prohibited

Employment discrimination laws across Europe and North America protect job applicants from unfair treatment. Questions that directly or indirectly reference protected characteristics are not allowed.

These protected characteristics typically include: age, gender, sexual orientation, marital status, pregnancy, religion or belief, political affiliation, nationality or ethnic origin, disability or chronic illness, and working hours preferences.

The point isn’t that recruiters intentionally discriminate. The point is that certain questions, even when asked innocently, produce information that can (unconsciously) color the assessment. And that’s exactly what the law aims to prevent.

The 10 most common illegal questions

1. ‘Are you planning to have children?’

This is probably the most common illegal interview question. It doesn’t matter how you phrase it: questions about family planning, pregnancy, or childcare arrangements are off-limits. Indirect variants like ‘How do you feel about long hours?’ with a wink toward personal situations count too.

What you can ask: ‘Are you available for the hours this position requires?’ That’s the business need, without the personal information.

2. ‘How old are you?’ or ‘What year were you born?’

Age should play no role in selection. You may ask whether someone meets the legal minimum age for the role if one exists (for example, when working with hazardous materials).

3. ‘Where are you originally from?’

Questions about origin, nationality, or ethnic background are prohibited. You may ask whether someone has work authorization for the country, as that’s a business requirement.

4. ‘What is your religion?’ or ‘Do you celebrate Christmas?’

Religion and belief systems are protected. You cannot ask about someone’s faith, not even indirectly through questions about holidays or dietary preferences.

5. ‘Do you have a disability or chronic illness?’

Health-related questions are prohibited during the application phase. Only after a conditional offer can a company physician conduct a pre-employment medical, and only if the role places special demands on medical fitness.

6. ‘Are you married?’ or ‘Do you have a partner?’

Marital status is irrelevant to job performance. It doesn’t matter whether someone is married, cohabiting, single, or divorced.

7. ‘What is your sexual orientation?’

This should go without saying, but it still happens. Any question that directly or indirectly references sexual orientation is prohibited.

8. ‘Which political party do you vote for?’

Political affiliation is protected. Exception: if you’re applying to a political party or an organization with a specific political foundation.

9. ‘Do you have a criminal record?’

This is a gray area. For some positions (education, healthcare, security), background checks are mandatory. But a general question about criminal history is not appropriate during the interview.

10. ‘How many sick days did you take at your previous employer?’

Sick leave is confidential information. You cannot ask about someone’s illness history, not even through references.

The legal consequences

What happens if you ask illegal questions as a recruiter? The consequences can be significant.

• The candidate can file a complaint with the relevant equality body
• The body can rule that the company discriminated
• The candidate can claim damages through the courts
• The company suffers reputational damage, especially in tight labor markets

And the reputational risk might be the biggest. In an era where candidates share their experiences on Glassdoor, Indeed, and social media, a discriminatory interview experience can damage your employer brand.

How to do it right: better alternatives

The good news: for every prohibited question, there’s a legal alternative that gives you the same information about the candidate’s suitability.

Instead of: ‘Are you planning to have children?’

Ask: ‘This role requires regular availability on [specific days/times]. Can you commit to this?’

Instead of: ‘Where are you from?’

Ask: ‘Do you have work authorization for this country?’

Instead of: ‘Do you have health problems?’

Ask: ‘Can you meet the physical requirements of this role?’ (only if relevant)

The pattern is clear: focus on the job requirements, not personal circumstances.

Training and awareness for your team

Most illegal questions aren’t asked with bad intent. They come from ignorance, curiosity, or an attempt to keep the conversation light. That’s why training matters so much.

With full interview transcripts, you can read back exactly which questions were asked instead of relying on what anyone remembers. This makes it easier to provide targeted feedback.

AI summaries of conversations help you check whether problematic questions were asked after the fact. You don’t need to be present at every interview to maintain quality.

• Organize annual equal treatment training for everyone who conducts interviews
• Create a list of approved questions per role
• Use structured interviews: same questions, same order, for every candidate
• Have a colleague observe or listen in on interviews

Structured interviews as the solution

The best way to prevent illegal questions? Structured interviews. You prepare a fixed list of questions in advance, directly linked to the job requirements and competencies.

By recording conversations with omnichannel recording and having them automatically summarized, you create an audit trail. You can check exactly which questions were asked and whether the interview stayed within the rules.

The transparency feature links every observation to the exact moment in the conversation. This doesn’t just improve your assessment, it also protects you legally.

What if a candidate voluntarily shares personal information?

Sometimes a candidate spontaneously shares personal circumstances. ‘I just became a mother’ or ‘I have a chronic condition.’ What do you do?

The rule is simple: you may not use the information in your assessment. Gently steer the conversation back to the job requirements. Don’t record the personal information in your evaluation. And if you’re unsure: discuss it with your HR department.

With CRM data entry, you determine exactly which fields are filled in after a conversation. Personal information that isn’t relevant to the role simply isn’t recorded.

International differences

If you recruit internationally, you need to account for different legal frameworks. What’s prohibited in one country may be handled differently elsewhere. And vice versa.

• In the US, asking about salary history is increasingly banned at the state level
• In Germany, strict rules apply around questions about union membership
• In the UK, it’s prohibited to ask about ‘spent convictions’

When working with international candidates, enterprise-grade security helps you comply with privacy legislation across countries, including GDPR and local variants.

Training and awareness: structural prevention

Most illegal questions aren’t asked with bad intent. A hiring manager who asks ‘do you have children?’ often does so out of genuine interest, without realizing the legal consequences. That’s why training is important. Not one-time, but periodic. Every manager who conducts interviews must know which topics are off-limits and why.

An effective approach is sharing alternative phrasings. Instead of ‘are you planning to have children?’ ask ‘this role requires regular office attendance, does that fit your situation?’ The same information, but legally sound. AI tools can assist by analyzing conversations afterward and proactively flagging when a question falls in the risk zone.

Agencies that structurally address this don’t just protect themselves against claims. They create a more professional candidate experience. Candidates notice the difference between a well-structured conversation and a disorganized interview. That professionalism translates directly into a stronger reputation as an employer or agency.

It’s not just about individual questions, but about creating a culture where everyone understands where the boundaries lie. A clear protocol, combined with technological support, makes the difference between an agency that reactively solves problems and one that prevents them.

Organizations that take this seriously also benefit from better diversity outcomes. When discriminatory questions are eliminated from the process, candidates are evaluated on merit alone. That leads to a broader talent pool and stronger hiring decisions overall.