Shift differential & bonus overtime: 600 worked examples
A base hourly rate can miss part of the overtime premium when shift pay or an includable bonus raises the regular rate. Compare the math, download the examples, or use the free spreadsheet.
These are hypothetical teaching scenarios generated by SalarySteps. They are not a worker survey, an estimate of wage theft, or evidence about any employer. Updated October 18, 2026.
The $11.33 difference in one 48-hour example
At $25/hour for 48 hours, a $3 differential on 12 of those hours adds $36. An includable $100 bonus brings straight-time earnings to $1,336. The regular rate is $1,336 ÷ 48, kept unrounded during the calculation.
The additional half-time premium is $111.33. Using only the $25 base rate gives $100. The $11.33 difference is in the overtime premium alone: both versions already include all base earnings, the $36 differential and the $100 bonus.
Open this exact 48-hour example in the calculator. The total modeled gross pay is $1,447.33, before deductions.
What changes as the workweek gets longer?
Each row uses the same $25 base rate, $36 shift pay and $100 includable weekly bonus. The ordinary federal weekly model starts overtime after 40 worked hours.
| Hours worked | Full regular-rate premium | Base-rate-only premium | Difference | Check it |
|---|---|---|---|---|
| 36 | $0.00 | $0.00 | $0.00 | Open example |
| 40 | $0.00 | $0.00 | $0.00 | Open example |
| 45 | $70.06 | $62.50 | $7.56 | Open example |
| 48 | $111.33 | $100.00 | $11.33 | Open example |
| 60 | $272.67 | $250.00 | $22.67 | Open example |
Across the full parameter grid, the largest premium difference is $61.67 for one workweek. This maximum follows from the chosen inputs; it does not describe a typical worker or a typical paycheck.
Use the free weighted overtime spreadsheet
- Download the CSV spreadsheet and open it in Excel, LibreOffice Calc or Google Sheets. When importing, choose comma separation and allow formulas to be evaluated. The sheet uses English function names and comma argument separators.
- Edit only cells A2:G2: two pay rates and their worked hours, extra shift dollars per hour, eligible differential hours, and the includable bonus allocated to that week. Enter zero for anything that does not apply.
- Count each worked hour once. Differential hours are a subset of worked hours. Do not add the differential again if it is already included in either hourly rate.
- Cell H2 must say OK. The default row produces $1,248 straight-time earnings, 48 hours, a $26 regular rate, a $104 extra half-time premium and $1,352 total gross pay. If formulas appear as text, use your spreadsheet's formula import option or the browser calculator.
- Calculate each workweek separately. For a biweekly paycheck, duplicate row 2 into row 3, enter the second week's inputs, and add the two gross totals. Do not average the hours across weeks.
Keep the regular-rate formula unrounded; changing its display format to two decimals does not change its underlying value. The file contains one sample row, formulas and no macros or external data connections.
How the 600 scenarios were generated
The complete grid crosses six base rates ($15, $20, $25, $30, $40 and $50), five weekly hours (36, 40, 45, 48 and 60), five differential settings ($0 on 0 hours; $3 on 12 or 24 hours; $5 on 12 or 24 hours), and four includable bonuses ($0, $100, $120 and $250): 6 × 5 × 5 × 4 = 600 workweeks.
For each row, straight-time earnings = base rate × worked hours + differential × eligible hours + includable weekly bonus. The regular rate = straight-time earnings ÷ worked hours. The extra overtime premium = unrounded regular rate × 0.5 × hours over 40. The comparison premium = base rate × 0.5 × hours over 40. The difference is the full premium rounded to cents minus the comparison premium rounded to cents.
Both methods include all straight-time pay and extras. This comparison isolates the effect of leaving extras out of the premium rate. The CSV's regular_rate_display is rounded for readability; use the earnings and hours columns to reproduce the unrounded rate. Every row links to its exact calculator inputs.
This models covered nonexempt hourly work under the ordinary federal weekly rule. It excludes state daily or seventh-day overtime, exemptions, special rate agreements, healthcare 8-and-80 schedules, paid leave, taxes and deductions. Bonuses must already be properly allocated to one workweek. A result cannot establish legal entitlement or an employer violation.
Sources: U.S. DOL Fact Sheet 23; U.S. DOL Fact Sheet 56a; U.S. DOL Fact Sheet 56c. See the site methodology and shift differential guide.
Reuse the examples or embed the calculator
The modeled CSV data and spreadsheet are released under CC0. You may reuse them in payroll training, staff resources, articles and classes. Attribution is appreciated and optional. Please retain the hypothetical-data label and explain the model's limits.
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