Employment Law Basics for US Employers
US employment law is layered: federal statutes set a floor, state laws layer on top with broader protections, and local ordinances (cities and counties) add more. Federal compliance covers the basics; state and local compliance is where most enforcement happens. This guide covers what every US employer has to understand.
At-will employment
Every US state except Montana follows the at-will employment doctrine: either the employer or the employee can terminate the employment at any time, for any reason or no reason, with or without notice — subject to exceptions. The exceptions are where the law actually operates:
- Discrimination. Cannot terminate for membership in a protected class (race, color, religion, sex, national origin, age, disability, genetic information, etc., per Title VII, ADA, ADEA, GINA).
- Retaliation. Cannot terminate for exercising legal rights (filing a complaint, taking FMLA leave, reporting wage violations, participating in an investigation, whistleblowing).
- Public policy. Cannot terminate for refusing to commit a crime, serving on jury duty, or other publicly-protected activity.
- Contract. Cannot terminate in violation of an employment contract that requires cause, notice, or specified procedures.
- Implied contract / handbook. Some courts find implied employment contracts from handbook language or course of conduct; well-drafted handbooks include explicit at-will disclaimers.
Montana's Wrongful Discharge from Employment Act requires "good cause" after a probationary period. For all other states, at-will is the rule and the practical question is whether a termination falls into one of the exceptions.
FLSA: wage and hour
The federal Fair Labor Standards Act sets the floor for minimum wage, overtime, recordkeeping, and youth employment. Key requirements:
- Minimum wage. $7.25 per hour federal as of 2024. Many states and cities have higher minimums — the higher rate applies.
- Overtime. Non-exempt employees must be paid at 1.5x the regular rate for hours worked over 40 in a workweek. Some states require daily overtime (California: over 8 hours/day or 6 days/week).
- Regular rate. Includes hourly wage plus most non-discretionary bonuses, commissions, and shift differentials. Calculating the regular rate correctly is where many overtime miscalculations originate.
- Recordkeeping. Detailed records of hours worked, wages paid, and other employment data for at least 3 years; some categories require longer.
- Child labor. Restrictions on hours and occupations for workers under 18.
State wage-and-hour laws are often stricter. California, New York, Washington, Oregon, and Massachusetts have particularly aggressive state requirements (meal and rest breaks, daily overtime, prompt payment, pay statement detail).
Exempt vs non-exempt classification
Non-exempt employees are entitled to overtime; exempt employees are not. Misclassification — treating someone as exempt who legally isn't — is the most common and expensive FLSA violation.
To qualify as exempt under the most common (white-collar) exemptions, the employee must satisfy both:
- Salary basis test. Paid a predetermined salary that doesn't vary with quantity or quality of work, above the FLSA threshold (set by DOL regulation; check the current threshold at dol.gov before relying on a specific number, as it has been litigated and revised). Some states have higher salary thresholds.
- Duties test. Primary duties match one of the recognized exemptions: executive (manages two or more full-time employees, hires/fires authority), administrative (office or non-manual work directly related to business operations, exercises discretion on significant matters), professional (advanced knowledge in a field of science or learning), computer (specific technical roles), outside sales (regularly works away from employer's place of business).
Common misclassification pitfalls: paying salary doesn't make someone exempt (must also pass duties test); calling someone a "manager" doesn't make them exempt if they don't actually manage; assistant managers in retail/food service rarely pass the duties test; lower-paid IT roles often don't qualify under the computer exemption.
Misclassification penalties include back wages (often two years, three if willful) plus liquidated damages doubling the amount, plus attorneys' fees. Class actions and DOL audits compound exposure.
Anti-discrimination laws
Federal protections, with employer-size thresholds:
- Title VII (Civil Rights Act of 1964). Race, color, religion, sex (including pregnancy, sexual orientation, gender identity), national origin. Applies to employers with 15+ employees. Enforced by EEOC.
- ADA (Americans with Disabilities Act). Disability discrimination; requires reasonable accommodation unless undue hardship. 15+ employees.
- ADEA (Age Discrimination in Employment Act). Age 40+. 20+ employees.
- GINA (Genetic Information Nondiscrimination Act). Genetic information. 15+ employees.
- Equal Pay Act. Equal pay for substantially equal work regardless of sex. All employers covered by FLSA.
- USERRA. Military service members. All employers.
- Section 1981. Race discrimination in contracts, including employment. All employers.
State laws often extend protections (sexual orientation, gender identity were widely protected at state level before the Supreme Court's 2020 Bostock decision extended Title VII), cover smaller employers, or add categories (marital status, political affiliation, off-duty conduct, salary history). Local ordinances add further (some cities prohibit criminal-history inquiries pre-offer — "ban the box").
Harassment
Harassment based on a protected characteristic is a form of discrimination under Title VII and related state laws. Two recognized theories:
- Quid pro quo. Employment decisions conditioned on submission to harassment (typical sexual harassment context).
- Hostile work environment. Conduct severe or pervasive enough to alter the conditions of employment.
Employer liability depends on the harasser. For supervisor harassment resulting in a tangible employment action (termination, demotion), the employer is strictly liable. For supervisor harassment without tangible action, the employer can assert an affirmative defense (Faragher/Ellerth) showing it had effective anti-harassment policies and the complainant unreasonably failed to use them. For co-worker or third-party harassment, the employer is liable if it knew or should have known and failed to take prompt remedial action.
Practical compliance: written anti-harassment policy with reporting mechanism, periodic training (required in some states for all employees, others only for supervisors, others not at all), prompt investigation of complaints, documented remedial action when warranted. California, New York, Connecticut, Delaware, Illinois, and Maine require harassment training for most employers.
Leave laws
FMLA (Family and Medical Leave Act). Federal. 50+ employees within 75 miles. Eligible employees (12 months of service, 1,250 hours in the prior 12 months) get up to 12 weeks unpaid leave per year for serious health condition (self or family), birth/adoption, or military exigency. Employer must maintain health benefits and reinstate to same or equivalent position.
State family/medical leave. Many states have their own laws with broader coverage, paid benefits, or both. California, New York, New Jersey, Massachusetts, Washington, Connecticut, Colorado, Oregon, Maryland, and others have or are implementing state paid family and medical leave programs.
Sick leave. No federal requirement. Many states and cities require paid sick leave accrual (typically 1 hour per 30-40 hours worked).
Pregnancy. Pregnancy Discrimination Act prohibits discrimination; Pregnant Workers Fairness Act (2023) requires reasonable accommodation for pregnancy-related conditions.
Bereavement, jury duty, voting, military. Some required by state law; otherwise governed by company policy.
I-9 verification and work authorization
Federal law (IRCA) requires every US employer to verify each new hire's identity and authorization to work in the United States. Form I-9 must be completed within three business days of hire. Employee provides documentation from List A (proves both identity and work authorization, e.g., US passport) or one from List B plus one from List C (identity plus work authorization).
The employer must examine the original documents (or for remote hire under current rules, follow the alternative procedure if eligible — check current USCIS guidance), record document information on the I-9, and retain the form for the longer of three years after hire or one year after termination.
E-Verify is a voluntary federal program (mandatory for federal contractors and in some states) that confirms work authorization against government databases. Enrollment is at e-verify.gov.
I-9 audits are conducted by ICE. Penalties for I-9 violations range from hundreds to thousands of dollars per form per violation, plus knowing-hire penalties for unauthorized workers.
Required posters and notices
Federal law requires specific posters in conspicuous locations at every worksite. Common required posters (downloads at dol.gov/agencies/whd/posters): FLSA minimum wage, OSHA "It's the Law", FMLA, EEO is the Law, USERRA, polygraph protection, employee polygraph protection. Posters must be in English; in some workplaces, Spanish or other-language versions are also required.
State labor departments require additional posters — workers' compensation, state minimum wage, state unemployment insurance, paid sick leave (where applicable). Most state labor agencies publish required posters on their websites.
For remote workers, "conspicuous location" requirements are typically satisfied by electronic distribution (intranet, email, employee portal).
Employee handbook
An employee handbook is not legally required but is the cheapest risk-management document an employer can have. Core sections:
- At-will disclaimer. Explicit statement that employment is at-will and the handbook is not a contract.
- EEO and anti-harassment policies. With reporting mechanism.
- Code of conduct. Expected behavior, conflicts of interest.
- Compensation and benefits. Pay periods, overtime policy, benefit eligibility, paid time off.
- Leave policies. Required leave types and any voluntary leave the company offers.
- Workplace policies. Attendance, tardiness, dress code, use of company equipment, remote work, drug and alcohol policy.
- Technology and information. Acceptable use, confidentiality, social media, monitoring disclosure.
- Discipline and termination. Procedures (kept flexible to preserve at-will), final pay rules.
- Safety. Workplace safety policy, reporting injuries.
- Acknowledgment. Signed receipt of handbook.
Update the handbook annually and any time material law changes. Reissue with acknowledgment to all employees after significant updates.
Terminations
Termination is the single highest-litigation-risk event in employment law. The basics:
- Documented performance issues. A documented record of warnings, performance plans, and policy violations is far stronger evidence than recollection. Even at-will terminations are easier to defend with documentation.
- Consistent treatment. Disparate-treatment claims arise when similarly-situated employees are treated differently. Apply policies consistently and document the basis for differences.
- Final paycheck. State law sets the deadline. Some states require same-day payment for involuntary termination (California). Failure to pay timely can trigger waiting-time penalties (in California, up to 30 days of additional wages).
- Accrued PTO. Some states require payout of accrued unused vacation; others don't. Handbook policy controls within state-law minimums.
- Separation agreement. When offering severance, get a release of claims in exchange. ADEA (age) waivers require specific disclosures and time periods (21 days to consider, 7 days to revoke, for individual terminations; 45 days for group RIFs — per OWBPA).
- COBRA notice. For employers with 20+ employees, notice of continuation coverage rights within statutory deadline.
- WARN Act. Federal Worker Adjustment and Retraining Notification Act: 100+ employee employers must give 60 days notice before mass layoff or plant closing meeting statutory thresholds. State mini-WARN acts impose additional requirements (California's is broader than federal).
Unemployment and workers' comp
Unemployment insurance is a state-administered program funded by employer payroll taxes (federal FUTA plus state). When a former employee files a claim, the employer responds with information about the separation; the state agency decides eligibility. Terminations for misconduct typically disqualify; layoffs and lack-of-work separations qualify. Each successful claim increases the employer's state unemployment tax rate.
Workers' compensation is mandatory in nearly every state for nearly every employer with employees. It's a no-fault system: workers injured on the job receive medical care and partial wage replacement regardless of fault; in exchange, employees generally cannot sue the employer in tort. Premiums depend on payroll, industry classification, and experience modifier. Failure to carry workers' comp where required is one of the few employment violations that can produce criminal liability for the owner.
Key federal agencies
- DOL (Department of Labor). FLSA, FMLA, OSHA, ERISA, wage-and-hour enforcement.
- EEOC (Equal Employment Opportunity Commission). Title VII, ADA, ADEA, GINA discrimination charges.
- NLRB (National Labor Relations Board). Union activity, concerted protected activity (extends to non-union workplaces).
- OSHA (Occupational Safety and Health Administration). Workplace safety.
- USCIS / ICE. Work authorization and I-9.
- OFCCP. Federal contractor affirmative action and discrimination.
- IRS. Payroll tax, worker classification (see classification), benefits compliance.
Common mistakes
- Treating salaried employees as exempt. Salary alone doesn't establish exemption; the duties test also matters. Most expensive single area of FLSA exposure.
- Off-the-clock work. Letting non-exempt employees work email, check Slack, or take calls outside scheduled hours without compensation.
- Inadequate timekeeping. "Hourly employee but we don't really track hours" produces both wage-and-hour claims and impossible-to-defend defenses when a claim is filed.
- Missing or stale handbooks. Handbook drafted years ago, never updated for law changes; or no handbook and ad-hoc policies inconsistently applied.
- Failure to document. Termination based on "performance issues" with no contemporaneous documentation looks like pretext.
- Ignoring state and local laws. Federal compliance is necessary but not sufficient in most jurisdictions.
- Treating contractors as employees (or vice versa). See classification.
- Mishandling reasonable accommodation requests. ADA requires interactive process; refusing without engagement is independently actionable.
- Retaliation after a complaint. The retaliation claim is often stronger than the underlying complaint. Once a complaint is on the record, performance management of the complainant must be airtight.
FAQ
How many employees before federal employment laws apply? Varies: ADEA at 20, Title VII/ADA at 15, FMLA at 50 (within 75 miles), FLSA wage-and-hour at one. Some state laws cover smaller employers.
Can I terminate someone for any reason in an at-will state? Almost. Not for a protected reason (discrimination, retaliation, public policy) and not in breach of a contract.
Do I have to give a reason for termination? Not legally required in at-will states (except where contract provides otherwise). Practically, vague or shifting reasons strengthen wrongful termination claims; document the actual reason and stick to it.
Are exit interviews required? No, anywhere. Optional management practice.
Can I require references be in writing? Yes, and most lawyers recommend providing only dates of employment and position, declining to give substantive references, to limit defamation exposure.
Are non-competes enforceable? Depends heavily on state. California voids most employee non-competes; many states limit by judicial reasonableness review; federal FTC regulation has been litigated. Always check current state law and federal status before relying.