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Cancellation Refund
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New Policy Premium
Mid-term start prorated cost
Daily / Custom Rate
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Full annual policy premium amount
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Typically 365 (annual) or 180 (6-month)
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Number of days coverage was active
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Pro Rata Amount
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Sources & Methodology
Pro rata calculation method based on NAIC model regulations and standard insurance industry practice. Updated March 2026.
NAIC — Insurance Policy Cancellation Model Act
National Association of Insurance Commissioners model regulation for pro rata and short rate refund calculations
Insurance Information Institute — Policy Guide
Industry reference for understanding premium calculations, cancellations, and refund methods
Methodology: Daily rate = Annual premium ÷ Policy term days. Pro rata refund = Daily rate × Days remaining. Short rate refund = Pro rata refund × 90% (insurer retains 10% penalty). New policy prorated premium = Daily rate × Days of coverage needed. All calculations use exact day counts.
⏱ Last reviewed: March 2026
How Pro Rata Insurance Calculations Work
Pro rata is Latin for "in proportion." In insurance, it means your premium is calculated proportionally based on the exact number of days covered. It's the fairest method for both insurers and policyholders.
Pro Rata vs. Short Rate Cancellation
| Method | Who Uses It | Penalty | Example ($1,200/yr, cancel after 90 days) |
|---|---|---|---|
| Pro Rata | Insurer-initiated cancellations; many state-regulated policies | None | Refund: $1,200 × (275÷365) = $904.11 |
| Short Rate | Policyholder-initiated cancellations | ~10% of unearned premium | Refund: $904.11 × 90% = $813.70 |
When Pro Rata Applies
- Insurer cancels your policy — non-payment grace period expired, underwriting issues, fraud. Insurer must refund pro rata in most states.
- You switch insurers mid-term — overlap avoidance. Calculate exact refund due from old insurer.
- New policy mid-term start — your first premium covers only partial period until renewal date.
- Coverage increase mid-term — additional premium is prorated for remaining days.
Daily Rate = Annual Premium ÷ Policy Days | Refund = Daily Rate × Days Remaining
Example: $1,200 annual premium, 365-day policy, cancel after 90 days
Daily rate = $1,200 ÷ 365 = $3.29/day
Days remaining = 365 − 90 = 275 days
Pro rata refund = $3.29 × 275 = $904.11
Daily rate = $1,200 ÷ 365 = $3.29/day
Days remaining = 365 − 90 = 275 days
Pro rata refund = $3.29 × 275 = $904.11
💡 State Regulations: Many states require insurers to refund on a pro rata basis even when the policyholder cancels, prohibiting short rate penalties. Always check your state's insurance department website or your policy's declarations page to know which method applies to your policy.
Frequently Asked Questions
Pro rata means proportional — your premium is charged or refunded exactly in proportion to the days of coverage. Cancel a 365-day $1,200 policy after 90 days, and you receive a refund for exactly 275/365 of the premium. Pro rata is the fairest method and is required by law for insurer-initiated cancellations in most states.
Pro rata refund = (Days remaining ÷ Total policy days) × Annual premium. Or equivalently: daily rate × days remaining. Example: $1,200 annual premium, cancel with 275 days left on a 365-day policy. Refund = (275 ÷ 365) × $1,200 = $904.11. The daily rate is $3.29/day. Our calculator does this instantly for any inputs.
Short rate cancellation is when the insurer retains a penalty (typically 10% of the unearned premium) when you cancel early. Using the same example: $904.11 pro rata refund × 90% = $813.70 short rate refund. The insurer keeps $90.41 as a cancellation penalty. Short rate is less common now — many states prohibit it or require advance disclosure. Check your policy.
New policy prorated premium = (Days until renewal ÷ Total policy days) × Annual premium. If your annual premium is $1,200 and you start coverage 90 days before your renewal date, your initial premium is (90 ÷ 365) × $1,200 = $295.89. After the renewal date, you'll pay the full annual premium going forward.
Most homeowners insurance policies refund on a pro rata basis when you cancel, especially if you're switching to a new insurer or selling the home. If you cancel without replacement coverage, some insurers may apply a short rate penalty. When your mortgage lender is involved (they're named on the policy), the refund process may involve them directly — always coordinate with your lender.
Most insurance refunds arrive within 5–15 business days of cancellation. If you paid by credit card, the refund goes back to the card. If you paid by check or bank transfer, you'll receive a refund check. Some insurers apply the refund to your new policy's first payment if you're staying with the same company. If you haven't received your refund after 30 days, contact your insurer directly.
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