Attrition rate is the percentage of your workforce lost to departures over a set period, calculated by dividing total separations by average headcount and multiplying by 100. Unlike turnover, which counts how often positions cycle through replacements, attrition captures net headcount loss when people leave and their seats stay empty. The metric matters because a company shedding staff faster than it can absorb the gaps eventually runs into productivity, knowledge, and morale problems, and because federal law imposes specific obligations once those departures happen at scale.
How To Calculate Attrition Rate
You need three numbers from payroll: headcount on the first day of the period, headcount on the last day, and total departures in between. Average the beginning and ending counts, divide departures by that average, and multiply by 100.
A company that opens the quarter with 210 employees and closes with 190 has an average headcount of 200. Twenty departures divided by 200 gives a 10 percent attrition rate for the quarter. The formula works for any timeframe, but annualized figures are more useful for spotting trends and comparing against outside data.
What Counts as a “High” Rate
The Bureau of Labor Statistics tracks voluntary quit rates monthly through its Job Openings and Labor Turnover Survey. The 2025 annual average quit rate across all nonfarm workers was 2.0 percent per month, with private-sector employers slightly higher at 2.2 percent.1U.S. Bureau of Labor Statistics. Job Openings and Labor Turnover Survey – Table 22 Those are monthly figures, so they compound significantly over a year.
Rates vary sharply by industry. Leisure and hospitality employers ran at 3.9 percent monthly, roughly triple the government sector’s 0.8 percent.1U.S. Bureau of Labor Statistics. Job Openings and Labor Turnover Survey – Table 22 Manufacturing and financial services sat near 1.4 percent; professional and business services came in at 2.3 percent. If your rate significantly exceeds the benchmark for your sector, the pressure is almost certainly coming from inside the company rather than the market.
Types of Attrition
Not every departure means the same thing, and averaging them together makes the number less useful. Break the count into categories before you interpret it.
- Voluntary attrition: the employee decides to leave, either by resigning or by walking away. This category is the most sensitive to pay, management, and culture.
- Involuntary attrition: the employer initiates the separation through layoffs, position eliminations, or terminations for cause. These carry the heaviest regulatory obligations.
- Natural attrition: predictable exits like retirement or the end of a fixed-term contract. Easiest to plan for.
- Internal attrition: an employee transfers to a different department or business unit. The person stays on payroll, but the originating team still needs to backfill.
Constructive Discharge Sits Between the Two
Constructive discharge occurs when working conditions become so intolerable that a reasonable person would feel compelled to resign. Courts treat those resignations as if the employer fired the worker, which opens the door to wrongful termination claims. What looks like voluntary attrition on a spreadsheet may actually be an involuntary separation with legal exposure. If exit interviews reveal a pattern of complaints tied to the same manager, workload, or policy, that pattern deserves attention before it becomes a lawsuit.
What Each Departure Costs
Research consistently places the total cost of replacing an employee at roughly one-third of that person’s annual salary. About a third of that cost is direct spending on recruiting, onboarding, and temporary coverage. The remaining two-thirds is indirect: reduced team output, strained workloads on remaining staff, and the management time absorbed by hiring and training.
Staffing agency or recruiter fees typically run 15 to 30 percent of the new hire’s first-year salary. Vacancy costs hit harder than most companies realize: when a revenue role sits open, the lost output shows up in weekly sales figures or billable hours, and when a support role goes unfilled, the cost spreads across the remaining team through overtime, errors, and burnout that seeds the next round of resignations. High attrition also drives up an employer’s state unemployment insurance tax rate, since experience rating charges higher premiums to companies with more frequent benefit claims against their accounts.2U.S. Department of Labor. Experience Rating – Unemployment Insurance Conformity Requirements for State UI Laws
When Attrition Becomes a Mass Layoff: WARN Act Rules
Once departures shift from individual exits to group reductions, federal law imposes advance notice. The Worker Adjustment and Retraining Notification Act applies to employers with 100 or more full-time employees, or 100 or more employees who collectively work at least 4,000 hours per week.3Office of the Law Revision Counsel. 29 USC 2101 – Definitions; Exclusions From Definition of Loss of Employment Covered employers must give affected workers 60 days’ written notice before ordering a plant closing or mass layoff.
The triggering numbers are more nuanced than many employers assume. A plant closing activates the notice when a shutdown causes 50 or more employees at a single site to lose their jobs within a 30-day window. A mass layoff triggers the requirement at either 500 or more employees at one site, or at least 50 employees who also make up at least 33 percent of the site’s workforce.3Office of the Law Revision Counsel. 29 USC 2101 – Definitions; Exclusions From Definition of Loss of Employment That combined 50-employee-and-33-percent rule catches companies that assumed they were too small.
Penalties for skipping notice are steep. An employer that violates the 60-day requirement owes each affected employee back pay and benefits for every day of the violation, up to 60 days. There is also a civil penalty of up to $500 per day payable to the local government, unless the employer pays all affected employees in full within three weeks of ordering the layoff.4Office of the Law Revision Counsel. 29 USC 2104 – Liability Many states have their own mini-WARN laws with lower thresholds and longer notice periods.
Discrimination Exposure in Reductions
Even a well-intentioned layoff can create liability if the workers selected skew toward a protected group. Under Title VII, a workforce reduction that disproportionately affects employees of a particular race, sex, religion, or national origin can trigger a disparate impact claim. The employer’s defense requires showing that the selection criteria were job-related and consistent with business necessity.5U.S. Equal Employment Opportunity Commission. Questions and Answers on EEOC Final Rule on Disparate Impact and Reasonable Factors Other Than Age Under the ADEA Vague justifications like “cultural fit” rarely survive that standard.
Age-related exposure is especially common in large reductions because senior employees often hold higher salaries, making them tempting targets for cost-cutting. The Age Discrimination in Employment Act protects workers 40 and older, and the Older Workers Benefit Protection Act adds procedural requirements when employers ask departing employees to sign a waiver releasing age discrimination claims.
Severance Waiver Rules for Group Layoffs
When a severance agreement asks employees to waive ADEA claims as part of a group layoff, the employer must follow strict rules or the waiver is unenforceable. The agreement must be written in plain language the employee can understand and must refer to the ADEA by name.6eCFR. 29 CFR 1625.22 – Waivers of Rights and Claims Under the ADEA The employee must receive something of value beyond what they were already owed, such as extra severance pay, and must be advised in writing to consult an attorney.
Timing is rigid. In a group termination, each employee gets at least 45 days to consider the agreement and a 7-day window after signing to revoke it. The 7-day revocation period cannot be shortened by agreement.6eCFR. 29 CFR 1625.22 – Waivers of Rights and Claims Under the ADEA The employer must also disclose the job titles and ages of everyone eligible for the program, plus the ages of employees in the same roles who were not selected. Skipping any of these steps voids the waiver, meaning the company paid severance and got no legal protection in return.
How Severance Pay Is Taxed
Severance is taxed as wages, not as a special category of income. The IRS classifies it as a supplemental wage subject to federal income tax withholding, Social Security tax, and Medicare tax. Employers can withhold at a flat 22 percent rate or combine severance with the employee’s regular wages and calculate withholding on the total. If an employee’s total supplemental wages for the calendar year exceed $1 million, withholding on the excess rises to 37 percent.7Internal Revenue Service. Publication 15 (2026), (Circular E), Employer’s Tax Guide
Companies that structure severance as installments stretching beyond the calendar year of separation need to consider Section 409A of the Internal Revenue Code. Noncompliant deferred compensation exposes the employee to a 20 percent additional tax on top of regular income tax, plus interest. The penalty applies at the plan level, so one poorly drafted severance agreement can contaminate an entire category of deferred compensation plans.
Post-Separation Duties Many Employers Miss
An employee’s last day triggers ongoing obligations that often surface only during an audit.
Final Wage Payment
Federal law does not require employers to hand over the final paycheck immediately.8U.S. Department of Labor. Last Paycheck Under the Fair Labor Standards Act, final wages including any earned overtime must be paid by the next regular payday.9U.S. Department of Labor. Handy Reference Guide to the Fair Labor Standards Act Many states impose tighter deadlines, with some requiring same-day payment for involuntary terminations. Whether accrued vacation or PTO must be included in the final check depends on state law and company policy, since no federal statute requires PTO payout.
Document Retention
Federal regulations require employers to keep Form I-9 employment verification documents for three years after the date of hire or one year after the employee’s last day, whichever comes later.10U.S. Citizenship and Immigration Services. 10.0 Retaining Form I-9 For someone who worked fewer than two years, the three-year-from-hire date controls; for longer-tenured employees, keep the form for one year after separation. The FLSA separately requires payroll records documenting wages, hours, and compensation data. Destroying records early weakens your position in any wage dispute or audit that follows.
Health Coverage Continuation
Employers with 20 or more employees who offer group health plans must provide departing workers with a COBRA election notice covering their right to continue coverage at their own expense. The plan administrator generally has 14 days after learning of the qualifying event to deliver the notice.11U.S. Department of Labor. Reporting and Disclosure Guide for Employee Benefit Plans Missing that window does not eliminate the obligation. It just creates exposure to penalties and lawsuits from former employees who lost coverage without being told they could have kept it.