Calculator
Example data table
| Scenario | Current | Claim | Fault | Reported-only | Renewal trend | Kept discounts | Projected Year 1 |
|---|---|---|---|---|---|---|---|
| Reported-only, not-at-fault | 1,200 | 0 | No | Yes | 6% | 13% | 1,285 |
| Moderate at-fault, no forgiveness | 1,200 | 4,500 | Yes | No | 6% | 5% | 1,565 |
| At-fault with forgiveness | 1,200 | 4,500 | Yes | No | 6% | 15% | 1,395 |
| High mileage and lapse | 1,000 | 2,500 | Yes | No | 8% | 3% | 1,365 |
Formula used
This calculator produces scenario estimates using structured adjustments. It helps compare outcomes across claim severity, renewal trend, discounts, and underwriting proxies.
- Back out kept discounts to estimate a base premium.
- Apply non-claim adjustments like trend, risk, and coverage.
- Apply claim adjustment scaled by fault, severity, and carrier.
- Re-apply kept discounts then add fees and add-ons.
- Project over years using the chosen decay schedule.
Base before discounts:
Base ≈ CurrentPremium / (1 − KeptDiscountPct)
Non-claim adjustment:
Adj = Trend + Coverage + Deductible + Risk + PriorClaims
Claim adjustment (year y):
ClaimAdj(y) = SurchargePct × DecayFactor(y)
Premium before fees and taxes:
Premium(y) = Base × (1 + Adj) × (1 + ClaimAdj(y)) × (1 − KeptDiscountPct)
Total:
Total(y) = (Premium(y) + PolicyFee + AddOns) × (1 + TaxPct)
How to use
- Enter your current annual premium from your latest bill.
- Add claim details, fault status, and reported-only choice.
- Set renewal trend and any planned coverage changes.
- Adjust deductibles and add-ons to match your renewal.
- Choose discounts you currently receive and their values.
- Click Calculate to view results above the form.
- Download CSV or PDF for documentation and sharing.
How claim severity shapes renewal pricing
Renewal impact often scales with claim size, claim type, and fault status. A larger paid claim can produce a higher surcharge than a reported-only incident because expected future loss costs rise. This calculator converts claim amount into a severity score using a threshold amount and applies a type factor so injury and liability events can weigh more than weather or comprehensive losses.
Surcharge duration and decay patterns
Many pricing models treat a claim as time-limited. To reflect that, the tool projects premiums across one to ten years and reduces the surcharge using linear, step-down, or slow decay. Year 1 typically shows the largest change, while later years soften as the claim ages and the applied adjustment declines.
Discount loss can matter as much as the surcharge
A claim may remove claim-free or safe-driver credits, even when the percentage surcharge is modest. The calculator tracks discounts you currently receive, estimates what remains after a claim, and re-prices the renewal accordingly. This highlights situations where preserving a discount can be more valuable than the direct claim adjustment.
Policy changes and market trend adjustments
Renewal pricing rarely changes for only one reason. Coverage upgrades, deductible changes, and broader market trends can shift the base premium before claim effects are applied. The model includes a renewal trend percent and deductible sensitivity so you can test whether a higher deductible or reduced coverage offsets some of the post-claim increase.
Using the scenario and waterfall charts for decisions
The scenario chart compares three paths: current premium, a no-claim renewal estimate, and a with-claim projection. The waterfall chart breaks Year 1 into non-claim adjustments, claim adjustment, discounts, fees, and taxes. For best use, run scenarios by changing one input. Save exports to compare outcomes and communicate pricing drivers. If you are shopping, adjust carrier behavior and discount loss to mirror quotes. Changes in assumptions can shift totals, so document each run.
FAQs
1) Does filing a claim always raise my premium?
Not always. Not-at-fault and reported-only events can have smaller impact, and some policies include forgiveness. Market trend and coverage changes may still move your renewal even without a surcharge.
2) What should I enter for a reported-only claim?
Set claim amount to zero and choose reported-only. The model applies a reduced severity assumption, but still allows discount loss if your claim-free credit typically drops after any reported incident.
3) How do prior claims affect the projection?
Prior claims add an additional adjustment per claim, representing repeat-loss behavior. Increasing the prior-claims field will compound impact and usually raises Year 1 and multi-year totals.
4) Why does the no-claim renewal estimate matter?
It separates general renewal movement from claim impact. Comparing no-claim versus with-claim helps you see how much of the change comes from trends, risk inputs, fees, and taxes.
5) Can I use this for different payment plans?
Yes. Select annual, semiannual, quarterly, or monthly, and add an installment fee if your carrier charges one. The tool converts the Year 1 total into a per-payment estimate.
6) Are the results exact quotes from insurers?
No. This is a scenario estimator using structured assumptions. Use it to compare options, document what-if cases, and understand drivers, then confirm final pricing with your carrier or broker.