Home / Blog / How to Calculate Overtime and Time-and-a-Half

How to Calculate Overtime and Time-and-a-Half

By Frame Sixty Labs · Last updated: July 24, 2026

The eight steps, in order

Overtime math is only hard because two different mistakes hide inside it: totaling time in base 10 when it should be base 60, and applying the 40-hour threshold to the wrong stretch of days. Work through these in order and both go away.

1. Confirm the work is overtime-eligible. Federal overtime rules apply to non-exempt employees. Being paid a salary does not automatically make someone exempt — exemption depends on duties and pay level, not on payment method.
2. Fix the workweek. A workweek is a fixed, recurring seven-day period — for example Sunday 00:00 through Saturday 23:59. It is set by the employer and does not have to match the calendar week or the pay period.
3. Total each day in H:MM. Clock-out minus clock-in, then remove any unpaid break.
4. Add the days into a weekly total. Carry 60 minutes into an hour, not 100.
5. Convert the weekly total to decimal. Minutes ÷ 60, added to the hours.
6. Split the week at 40 hours. Up to 40 is regular; the rest is overtime.
7. Work out the overtime rate. Regular rate × 1.5.
8. Multiply each bucket and add. That is gross pay for the week, before deductions.

What does a full worked week look like?

Here is a real-shaped week: five early shifts, each with a 30-minute unpaid lunch. Elapsed time is clock-out minus clock-in; paid time is what's left after the break comes out.

Add the paid column in H:MM to check the total: 8:15 + 8:45 = 17:00, plus 9:30 is 26:30, plus 8:00 is 34:30, plus 10:00 is 44:30. In decimal that's 44 + 30 ÷ 60 = 44.5 hours — and the decimal column adds to 44.50 as well, which is the check you want before touching money.

Now split at 40. Regular hours: 40.0. Overtime hours: 44.5 − 40 = 4.5.

How do you turn overtime hours into pay?

At a regular rate of $22.00 an hour, time-and-a-half is 22 × 1.5 = $33.00 an hour. Then:

• Regular pay: 40 × $22.00 = $880.00
• Overtime pay: 4.5 × $33.00 = $148.50
• Gross for the week: $1,028.50

Payroll systems often show a second route to the same number, and it's worth knowing because it makes audits easier. Pay every hour at straight time, then add a half-time premium on the overtime hours only: 44.5 × $22.00 = $979.00, plus 4.5 × $11.00 = $49.50, which is $1,028.50. Identical. If your two methods disagree, one of them has the hours wrong, not the rate.

Time-and-a-half rate reference

Multiply by 1.5 — nothing more. A few common rates, with what eight overtime hours would be worth at each:

Double time — 2× the regular rate — is not a federal requirement. Where it appears, it generally comes from a state rule, a union contract, or an employer's own holiday policy. Check your own terms rather than assuming it applies.

Why is overtime counted per week, not per paycheck?

This is the mistake that quietly costs people money. Under federal US rules the workweek stands alone — you cannot average two weeks together.

Take a biweekly pay period with 45 hours in week one and 35 hours in week two. The period total is 80 hours, so it looks like there's no overtime. But week one crossed 40 by 5 hours, and those 5 hours are overtime regardless of what week two looked like. At $20.00 an hour that's 5 × $30.00 = $150.00 of overtime pay plus 75 × $20.00 = $1,500.00 of regular pay — $1,650.00, not the $1,600.00 that averaging would produce.

Practical consequence: keep your totals per workweek, and start a fresh total the moment the workweek rolls over. If you're building the week day by day, our guide to calculating a weekly timesheet walks through the daily arithmetic.

Do unpaid breaks change the overtime total?

Yes, and this is where phantom overtime comes from. Unpaid breaks come out before anything is compared to 40 hours.

Say five 10:30 shifts, each with a 30-minute unpaid lunch, at $28.00 an hour. Done correctly, that's 10:00 paid per day, or 50.0 hours for the week: 40 × $28.00 = $1,120.00 plus 10 × $42.00 = $420.00, so $1,540.00. Skip the break deduction and the week reads 52:30, or 12.5 overtime hours: $1,120.00 + 12.5 × $42.00 = $1,645.00. That single missed step overstates the check by $105.00 — and because the error lands entirely in the overtime bucket, it's inflated at 1.5×, not at the base rate.

Short paid rest breaks generally do count as hours worked and stay in the total. It's the bona fide unpaid meal period that comes out.

How do you handle partial overtime hours?

Minutes don't vanish just because they're awkward. Convert them the same way you convert anything else — divide by 60 — and resist the urge to round early.

A week of 40:20 has 20 minutes of overtime. That's 20 ÷ 60 = 0.3333… hours. At a $33.00 overtime rate the correct amount is $11.00 exactly (a third of $33). Round the hours to 0.33 first and you get $10.89 — eleven cents short, every week it happens. Carry four decimal places through the multiplication and round only the final dollar figure.

The same discipline applies to the hours themselves: 8:20 is 8.33 hours, not 8.20. If that conversion is unfamiliar, what are decimal hours covers it properly.

Does a bonus change the overtime rate?

It can, and most overtime explainers skip it. Under federal US rules the overtime premium is based on the regular rate, which includes non-discretionary pay like production, attendance, or shift bonuses — not just the base hourly rate.

Worked example: 44 hours at $20.00 an hour plus a $60.00 production bonus for that week.

1. Straight-time earnings: 44 × $20.00 = $880.00, plus the $60.00 bonus, is $940.00.
2. Regular rate: $940.00 ÷ 44 = $21.3636…, about $21.36 an hour — higher than the $20.00 base.
3. Half-time premium on the 4 overtime hours: ($21.3636 ÷ 2) × 4 = $42.73.
4. Total: $940.00 + $42.73 = $982.73.

Using the $20.00 base instead would have produced a $40.00 premium — close, but not the same number. Truly discretionary bonuses, gifts, and most paid-time-off payments are treated differently. This is exactly the kind of detail worth confirming with your payroll department rather than guessing.

What about overnight shifts and the weekly split?

An overnight shift doesn't get special overtime treatment — it just needs the elapsed time calculated correctly first. A 21:45 → 06:15 shift is 8:30, found by adding 24 hours to the end time before subtracting. The full method is in how to calculate hours between two times.

The one thing to settle is which workweek an overnight shift belongs to when it straddles the boundary. Employers differ: some assign the whole shift to the day it started, others split the hours across both days. Pick the rule your employer uses and apply it consistently — switching methods mid-quarter is how reconciliation nightmares start.

Four 12-hour shifts in one week is a common healthcare pattern and a clean example: 4 × 12:00 = 48:00, so 40 regular and 8 overtime. At $30.00 an hour that's $1,200.00 + 8 × $45.00 = $1,560.00. Three 12-hour shifts is 36:00 — under the threshold, so no overtime at all.

Two mistakes worth checking for

• Base-10 time totals. Adding 8:45 and 8:45 on a phone calculator as 8.45 + 8.45 gives 16.90, implying 16 hours 54 minutes. The real answer is 17:30. Every minute of that gap eventually lands in the overtime bucket at 1.5×.
• "Comp time" instead of overtime pay. Under federal rules, giving private-sector non-exempt employees paid time off in place of overtime pay generally isn't permitted — the rules for public agencies differ. If this is being offered, get it confirmed in writing.

Some states also apply daily overtime — a premium after a set number of hours in a single day, regardless of the weekly total — and some have different thresholds for the seventh consecutive day. Those rules are jurisdiction-specific, so check your state labor agency rather than assuming the federal 40-hour rule is the whole picture.

Frequently asked questions

How do you calculate overtime pay?

Total the workweek, subtract 40 to get overtime hours, and pay those at 1.5× the regular rate. For 44.5 hours at $22.00: 40 × $22.00 = $880.00 plus 4.5 × $33.00 = $148.50, so $1,028.50 gross.

What is time-and-a-half of $20 an hour?

$30.00 an hour, because 20 × 1.5 = 30. Eight overtime hours at that rate come to $240.00.

Is overtime calculated per week or per pay period?

Per workweek, under federal US rules. A biweekly pay period gets two separate calculations. Working 45 hours one week and 35 the next produces 5 overtime hours, not zero — the weeks can't be averaged.

Do unpaid lunch breaks count toward overtime?

No — they're deducted before the week is compared to 40 hours. Missing a 30-minute unpaid lunch across five days adds 2.5 phantom hours, and those land in the overtime bucket at 1.5×. Short paid rest breaks generally do count as hours worked.

How do you calculate overtime on a partial hour?

Divide the minutes by 60, then multiply by the overtime rate. Twenty minutes is 0.3333 hours, and at $33.00 that's exactly $11.00. Rounding to 0.33 first pays $10.89 instead.

Does a bonus change the overtime rate?

It can. Non-discretionary bonuses are folded into the regular rate first. A 44-hour week at $20.00 plus a $60.00 bonus gives $940.00 of straight-time earnings and a regular rate of about $21.36, which raises the overtime premium above what the $20.00 base alone would produce.