Comprehensive vs third party car insurance calculator
Compare comprehensive and third party, fire and theft (TPFT) cover over a set period. See the premium difference, estimate how your vehicle's value changes, and consider your potential exposure if damage to your own car is not covered.
Typical: 10–20% per year. Adjust to suit your vehicle.
Assumptions and methodology
Premium difference is calculated from your inputs. Vehicle value after depreciation uses: Value(year n) = Initial value × (1 − depreciation%)^n. The potential own-damage exposure is the estimated vehicle value at each year (what you might not recover if you chose TPFT and had an at-fault accident). All figures are illustrative based on your inputs.
Common mistakes to avoid
- ✕Insuring for market value on the buildings sum insured rather than rebuild cost.
- ✕Assuming TPFT is always significantly cheaper — the premium gap varies.
- ✕Not factoring in depreciation when deciding how long to keep comprehensive cover.
- ✕Forgetting that TPFT does not cover at-fault damage to your own vehicle.
Frequently asked questions
Not always. The premium gap varies by insurer, vehicle, driver profile, and location. Sometimes comprehensive is only marginally more expensive. Always get quotes at both levels.
When the market value of your vehicle falls to a level where the additional comprehensive premium is disproportionate to the potential payout for own-damage. This varies by individual circumstances.
TPFT covers theft of the vehicle itself. Personal items inside the car are typically covered under contents insurance (if you have a personal possessions extension) rather than motor insurance. Check your policy wording.
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Disclaimer
This is a simplified estimate based on the assumptions shown above. It isn't a quote, and a real insurer may arrive at a different figure. Use it as a starting point, then check the details with your insurer or adviser.