Standard statutory minimum in many regions is 28 days (including bank holidays).
Typically 37.5 or 40 hours.
Enter 52 for a full year. Enter fewer if starting or leaving mid-year.
Pro Rata Days Entitlement:–
Total Holiday Hours:–
Accrual Percentage:–
Understanding Pro Rata Holiday Entitlements
Calculating holiday entitlement for part-time workers or staff who start part-way through a leave year can be complex. "Pro rata" simply means "in proportion." Part-time employees are entitled to the same holidays as full-time employees, calculated proportionally based on the hours they work.
How the Calculation Works
The logic used in this calculator follows standard HR practices for determining leave allowance. The core formula is:
(Employee Hours / Full Time Hours) × Full Time Holiday Entitlement
The Components
Full-Time Entitlement: The total days a full-time employee gets per year (often 28 days including bank holidays in the UK).
Work Ratio: Calculated by dividing the employee's weekly hours by the standard full-time week (e.g., 20 hours / 40 hours = 0.5).
Duration Adjustment: If an employee only works part of the year (e.g., starts in July), the entitlement is further multiplied by the proportion of the year worked (Weeks Worked / 52).
Excel Formula for Pro Rata Holiday
If you are building a spreadsheet, you can use the following logic in Excel:
Assuming:
Cell A1: Full Time Entitlement (e.g., 28)
Cell A2: Employee Weekly Hours (e.g., 22.5)
Cell A3: Standard Full Time Hours (e.g., 37.5)
The Formula:=(A2/A3)*A1
Example Calculation
Let's look at a practical example of a part-time worker:
Full-time contract: 40 hours per week with 28 days of holiday.
Part-time employee: Works 24 hours per week.
Calculation: (24 ÷ 40) = 0.6 (or 60%).
Entitlement: 0.6 × 28 days = 16.8 days.
Most employers round up to the nearest half-day, but statutory regulations usually prevent rounding down.
Part-Year Workers
If an employee starts or leaves during the leave year, you must adjust the calculation. For example, if the employee in the example above only worked for 26 weeks (half a year), their entitlement would be 16.8 days ÷ 2 = 8.4 days.
Holiday Hours vs. Days
For employees working irregular shifts, it is often more accurate to calculate holiday entitlement in hours. This calculator provides both figures. The total holiday hours are calculated by converting the days entitlement back into hours based on the average length of a working day for that specific employee.
function calculateHoliday() {
// Get input values
var ftEntitlement = parseFloat(document.getElementById('ftEntitlement').value);
var ftHours = parseFloat(document.getElementById('ftHours').value);
var ptHours = parseFloat(document.getElementById('ptHours').value);
var weeksWorked = parseFloat(document.getElementById('weeksWorked').value);
// Validation
if (isNaN(ftEntitlement) || isNaN(ftHours) || isNaN(ptHours) || isNaN(weeksWorked)) {
alert("Please enter valid numbers in all fields.");
return;
}
if (ftHours <= 0) {
alert("Full-time hours must be greater than 0.");
return;
}
// 1. Calculate the Ratio of part-time to full-time
var fteRatio = ptHours / ftHours;
// 2. Calculate the Ratio of the year worked (if not 52 weeks)
var yearRatio = weeksWorked / 52;
// 3. Calculate Days Entitlement
// Formula: FT_Entitlement * FTE_Ratio * Year_Ratio
var proRataDays = ftEntitlement * fteRatio * yearRatio;
// 4. Calculate Hours Entitlement
// To get hours, we determine the value of a 'day' in hours for the full-time role first?
// Actually, simpler logic:
// Total Annual Hours Entitlement = (PT_Hours * Weeks_Worked) * (Percentage of time that is holiday)
// HR Standard approach: Take the proRataDays and multiply by the average length of the employee's working day.
// Employee's average day length = ptHours / 5 (assuming 5 day standard) or simply base it on the FTE ratio.
// Alternative method for Hours:
// Full time holiday hours = ftEntitlement * (ftHours / 5) (Assuming standard 5 day week for the entitlement basis)
// Employee holiday hours = Full Time Holiday Hours * FTE_Ratio * Year_Ratio
// Let's assume the standard 'day' definition comes from the FT contract dividing by 5
var ftDayLength = ftHours / 5;
var totalHolidayHours = proRataDays * ftDayLength;
// Wait, if someone works 1 day a week (8 hours), and FT is 5 days (40 hours).
// Ratio = 0.2.
// Entitlement = 28 * 0.2 = 5.6 days.
// In hours, that should be 5.6 * 8 hours = 44.8 hours.
// My previous formula: 5.6 * (40/5) = 5.6 * 8 = 44.8. This works.
// Rounding
// Statutory usually allows rounding up, never down. We will show 2 decimal places.
var displayDays = proRataDays.toFixed(2);
var displayHours = totalHolidayHours.toFixed(2);
var percentOfFt = (fteRatio * 100).toFixed(1);
// Display Results
document.getElementById('resultDays').innerHTML = displayDays + " Days";
document.getElementById('resultHours').innerHTML = displayHours + " Hours";
document.getElementById('resultPercent').innerHTML = percentOfFt + "% of Full Time";
document.getElementById('results').style.display = "block";
}