Calculate earned premiums and refunds for policy cancellations.
Total Policy Days:–
Days Active (Earned):–
Daily Premium Rate:–
Earned Premium (Cost to Keep):–
Unearned Premium (Refund Amount):–
function calculateProRata() {
// Get input values
var premiumInput = document.getElementById('annualPremium').value;
var startInput = document.getElementById('policyStart').value;
var endInput = document.getElementById('policyEnd').value;
var cancelInput = document.getElementById('cancelDate').value;
var errorDiv = document.getElementById('errorDisplay');
var resultDiv = document.getElementById('resultBox');
// Reset display
errorDiv.style.display = 'none';
resultDiv.style.display = 'none';
// Basic validation
if (!premiumInput || !startInput || !endInput || !cancelInput) {
errorDiv.innerHTML = "Please fill in all fields correctly.";
errorDiv.style.display = 'block';
return;
}
var premium = parseFloat(premiumInput);
if (isNaN(premium) || premium <= 0) {
errorDiv.innerHTML = "Please enter a valid premium amount.";
errorDiv.style.display = 'block';
return;
}
// Date logic
var startDate = new Date(startInput);
var endDate = new Date(endInput);
var cancelDate = new Date(cancelInput);
// Normalize time to midnight to ensure accurate day calculation
startDate.setHours(0,0,0,0);
endDate.setHours(0,0,0,0);
cancelDate.setHours(0,0,0,0);
// Validation logic for dates
if (endDate <= startDate) {
errorDiv.innerHTML = "Policy expiration date must be after the start date.";
errorDiv.style.display = 'block';
return;
}
if (cancelDate endDate) {
errorDiv.innerHTML = "Cancellation date must be within the policy period.";
errorDiv.style.display = 'block';
return;
}
// Calculate time differences in milliseconds
var oneDay = 24 * 60 * 60 * 1000;
var totalPolicyTime = endDate – startDate;
var activeTime = cancelDate – startDate;
var remainingTime = endDate – cancelDate;
// Convert to Days
var totalDays = Math.round(totalPolicyTime / oneDay);
var daysActive = Math.round(activeTime / oneDay);
var daysRemaining = Math.round(remainingTime / oneDay);
// Calculate Ratios
var dailyRate = premium / totalDays;
var earnedPremium = dailyRate * daysActive;
var unearnedPremium = dailyRate * daysRemaining;
// Display Results
document.getElementById('totalDaysDisp').innerHTML = totalDays + " days";
document.getElementById('daysActiveDisp').innerHTML = daysActive + " days";
document.getElementById('dailyRateDisp').innerHTML = "$" + dailyRate.toFixed(2) + " / day";
document.getElementById('earnedPremiumDisp').innerHTML = "$" + earnedPremium.toFixed(2);
document.getElementById('refundDisp').innerHTML = "$" + unearnedPremium.toFixed(2);
resultDiv.style.display = 'block';
}
How to Calculate Pro Rata Insurance Premium
Understanding how insurance refunds work is essential for policyholders and agents alike. When an insurance policy is cancelled before its expiration date, the insurer must determine how much money to return to the policyholder. This is known as the "unearned premium." The most common method for calculating this refund is the Pro Rata method.
What is Pro Rata Cancellation?
A pro rata cancellation calculates the premium refund based strictly on the number of days the policy was in force versus the number of days remaining. Unlike "short-rate" cancellations, which include a penalty fee for early cancellation, pro rata is a fair, proportional distribution of the premium.
This method is typically used when:
The insurance company cancels the policy (e.g., due to underwriting reasons).
The policy is being rewritten or replaced with the same carrier.
Specific state laws require pro rata refunds for insured-requested cancellations.
The Pro Rata Formula
To calculate the return premium manually, you need three key pieces of data: the total premium, the total days in the policy term, and the number of days the policy was active.
1. Daily Rate = Total Premium ÷ Total Policy Days
2. Earned Premium = Daily Rate × Days Active
3. Unearned Premium (Refund) = Total Premium – Earned Premium
Example Calculation
Let's look at a concrete example to illustrate how the math works:
Annual Premium: $1,200
Policy Term: January 1st to January 1st (365 days)
Cancellation Date: July 1st
First, we calculate the daily rate: $1,200 ÷ 365 = $3.29 per day.
Next, we determine how many days the policy was active. From January 1st to July 1st is typically calculated as 181 days (in a non-leap year).
Finally, the Earned Premium is $3.29 × 181 = $595.49. The refund (Unearned Premium) would be $1,200 – $595.49 = $604.51.
Why Use a Pro Rata Calculator?
While the math seems straightforward, manual calculations often lead to errors due to day-counting mistakes (e.g., forgetting leap years or miscounting days in specific months). Our calculator above automates the date logic to ensure you get a precise figure instantly.
Earned vs. Unearned Premium
It is important to understand the terminology used in insurance accounting:
Earned Premium: The portion of the premium that applies to the time period that has already passed. The insurance company keeps this money because they provided coverage during this time.
Unearned Premium: The portion of the premium covering the future period after the cancellation date. This is the amount returned to the policyholder.
Pro Rata vs. Short Rate
Not all cancellations result in a full pro rata refund. If you (the insured) choose to cancel a policy mid-term without a valid reason (like selling the insured vehicle), the insurer may apply a Short Rate calculation. This imposes a penalty, often around 10% of the unearned premium, to cover administrative costs.
Always check your policy documents or ask your agent to confirm if your cancellation will be processed on a pro rata or short rate basis before finalizing the cancellation.