Turnover Rate Calculation by Month (Formula)

To calculate turnover rate by month, divide the number of employees who left during that month by the average number of employees on payroll during the same month, then multiply by 100. For example, if 5 employees left in March and you had an average of 100 employees, your monthly turnover rate is 5%.

Formula

The standard monthly turnover rate formula is:

Turnover Rate (%) = (Number of Separations ÷ Average Number of Employees) × 100

Where:

• Number of Separations – total employees who left during the month (voluntary resignations, terminations, retirements, etc.)
• Average Number of Employees – typically (headcount at start of month + headcount at end of month) ÷ 2

This formula gives a percentage that represents the proportion of your workforce that turned over in that single month.

Worked Example

Using the calculator defaults: start with 100 employees, hire 10, and 5 leave.

1. End-of-month headcount = 100 + 10 − 5 = 105
2. Average headcount = (100 + 105) ÷ 2 = 102.5
3. Turnover rate = (5 ÷ 102.5) × 100 = 4.878% ≈ 4.9%

So the monthly turnover rate is 4.9%.

Why Calculate Monthly Instead of Annually?

Monthly turnover gives you a more current, actionable snapshot than an annual figure. Annual rates can hide seasonal spikes or sudden retention problems. For example, an annual rate of 12% might look stable, but a single month with 8% turnover could signal a serious issue. Monthly tracking helps you spot trends early and evaluate the impact of new policies, management changes, or hiring waves.

It also aligns with other monthly HR metrics like absenteeism, overtime, and recruiting costs, making it easier to correlate causes and effects.

How to Choose the Right Headcount Method

The most common approach is the simple average of beginning and ending headcount. However, if your staffing fluctuates significantly during the month, you might use a more precise average:

• Simple average – (start + end) ÷ 2. Best for stable workforces.
• Sum of daily headcounts ÷ days in month – more accurate when hiring or departures are unevenly spread.
• Payroll-based average – sum of headcounts on each pay period divided by number of pay periods. Useful if you run biweekly or semi-monthly payroll.

Whichever method you choose, apply it consistently so month-to-month comparisons remain valid.

Common Mistakes and Pitfalls

• Using end-of-month headcount only – this ignores mid-month changes and can understate or overstate turnover.
• Counting all separations the same – some companies exclude layoffs or retirements to focus on “voluntary” turnover. Decide what you want to measure and document it.
• Mixing part-time and full-time – if you have many part-timers, consider using full-time equivalents (FTEs) instead of headcount.
• Rounding too early – keep at least one decimal place in intermediate steps to avoid significant error.
• Comparing to annual benchmarks – a 5% monthly rate is not “60% annual.” Annualizing requires compounding, not simple multiplication.

How to Annualize a Monthly Rate

If you want to estimate an annual rate from a single month, do not just multiply by 12. That ignores compounding. Instead, use the formula:

Annualized Turnover = 1 − (1 − Monthly Rate)^12

For example, a 4.9% monthly rate gives: 1 − (0.951)^12 ≈ 1 − 0.547 = 0.453, or 45.3%. This is much lower than 4.9% × 12 = 58.8%. The compounding formula is more accurate if the monthly rate stays constant.

Limitations of the Monthly Rate

The monthly turnover rate is a lagging indicator – it tells you what happened, not why. It also assumes a linear workforce change, which may not hold during rapid expansion or contraction. For small companies (say, under 20 employees), a single departure can swing the rate dramatically, so interpret with caution. Additionally, the rate does not distinguish between high-performing and low-performing leavers, nor does it capture the cost of replacement. Use it alongside retention metrics (e.g., percentage of new hires who stay 12 months) to get a fuller picture.

Frequently Asked Questions

What is a good monthly turnover rate?

There is no universal benchmark – it varies by industry, role, and location. For example, retail and hospitality often see higher turnover than government or utilities. Instead of comparing to a generic number, track your own trend over time and compare with industry-specific data if available.

Should I include interns or temporary workers?

It depends on your goal. If you want to measure core workforce stability, exclude temporary staff and interns. If you want to capture total churn, include them. Whichever you choose, be consistent and note it in your reporting.

How do I calculate turnover rate if I only have year-end data?

You cannot accurately reconstruct monthly rates from annual totals unless you have monthly headcount records. If you have only annual data, calculate an annual rate using the same formula: total separations ÷ average annual headcount × 100.

What is the difference between turnover and attrition?

Turnover includes all separations – voluntary and involuntary. Attrition usually refers only to voluntary departures, often when a position is not immediately backfilled. Attrition is a subset of turnover.

Does the monthly rate include new hires who leave within the same month?

Yes, if they are counted as separations. Some organizations track “first-year turnover” separately, but the standard formula counts any separation during the month, regardless of tenure.

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in t | Total employees at start of month | - | 100 | 0
in h | Employees hired during month | - | 10 | 0
in l | Employees who left during month | - | 5 | 0
out avg | Average employees | - | (t + (t + h - l)) / 2 | 1
out rate | Monthly turnover rate | % | l / avg * 100 | 1