Prorated Bonus Calculator
Calculate a prorated bonus for new hires, leavers, unpaid leave, part time schedules and partial year eligibility.
Last reviewed 10 September 2026
Calculate a part-period bonus
Calendar mode includes both endpoints, counts leap days and clips service to the bonus period. It includes weekends and holidays. Manual mode uses your plan’s own units. Excluded leave cannot exceed eligible service.
What is a prorated bonus?
A prorated bonus is a bonus reduced in proportion to how much of the performance period you were actually eligible for. Work nine months of a twelve-month plan and you receive 9/12 — 75% — of what you would otherwise have earned. Performance multipliers are then applied to that reduced figure.
The formula is trivial. What is not trivial is how your employer counts the time — by calendar days, by whole months, or by payroll periods. On a $100,000 salary with a 20% target, those three methods can be $1,280 apart for the same joining date.
Related tools and next steps
Worked example: a mid-year starter
An employee eligible for a $10,000 annual bonus who started on 1 July is in the plan for 184 of 365 days. The prorated bonus is 10,000 × (184 ÷ 365) = $5,041.
Some plans prorate by whole months instead of days — check your policy.
The three counting methods
| Method | How it counts | Joined 12 April |
|---|---|---|
| Calendar days | Eligible days ÷ days in period. Most precise, and the usual default in modern HR systems. | 264/365 = 72.3% |
| Whole months | Complete months ÷ 12. A partial month usually counts only if you started before a cut-off, often the 15th. | 8/12 = 66.7% |
| Payroll periods | Eligible periods ÷ total periods. | 19/26 = 73.1% |
What triggers proration
Where the cap applies
Multiplication order does not change the result, with one exception: a cap is not a multiplier. Nearly all plans cap against the prorated target, which is the consistent reading — you cannot earn 150% of a bonus you were only eligible for three quarters of.
$90,000 salary × 15% target = $13,500 · × 264/365 days = $9,763 prorated target · × 1.10 company performance = $10,738 · cap of 200% ($19,526 on the prorated target) not reached. Educational gross estimate only.
Full detail in proration explained. For scorecard plans, the STIP calculator handles eligibility alongside company and individual factors.
Prorated bonus questions
How do you prorate a bonus by days?
Multiply full target bonus by eligible days divided by total period days, then apply performance or FTE factors if relevant.
Should I use daily or monthly proration?
Use the method written in the plan. Daily proration is more precise; monthly proration is simpler but less exact.
Do mid-year joiners get a full bonus?
Usually not. Most plans prorate the bonus for the portion of the period worked, unless the policy states a full bonus regardless of start date.
Is a bonus prorated for leavers?
It depends on the plan. Some pay a prorated bonus for time worked; others require active employment on the payment date, paying nothing to leavers.
Day-based or month-based proration?
Day-based is the most precise. Month-based proration rounds to whole months and is simpler but slightly less accurate.
How do you calculate a prorated bonus?
Multiply the full bonus by the fraction of the period you were eligible for. With day counting that is eligible days divided by days in the period; with month counting it is complete months divided by twelve. Apply the performance multiplier to the prorated figure, and apply any cap last.
What does prorated bonus mean?
A bonus reduced in proportion to the time you were actually eligible. Nine months of a twelve-month plan gives 75% of the full amount, before any performance multiplier.
Do I get a bonus if I joined mid-year?
Usually yes, prorated to your eligible service, provided you meet any minimum service condition. Some plans require three months of service before a bonus accrues, and some require you to have started before a fixed cut-off date.
Reviewed 20 August 2026 by the BonusPayCalc editorial team. Gross planning estimates only — not payroll, tax, legal or HR advice. See methodology for how formulas are chosen, or report a correction.