No-Claims Bonus Calculator
A no-claims bonus rewards claim-free years with a growing discount on your insurance premium. The math is simple: the discounted premium is the base premium times one minus the discount percentage, and the saving is the base premium times the discount percentage. This calculator shows your current discounted premium and saving, then previews next year's figures using the next bonus level's discount, so you can see the value of staying claim-free. Both discount percentages are user-editable inputs because every insurer's bonus schedule differs.
No-claims bonus formula
Discounted premium = base premium * (1 - discount / 100)
Saving = base premium * (discount / 100)
Next-year premium = base premium * (1 - next discount / 100)
Extra saving = discounted premium now - next-year premium
The saving rises with the discount percentage. The extra saving shows the additional benefit of moving up one bonus level after another claim-free year.
No-claims bonus context
- Discounts grow with consecutive claim-free years up to an insurer maximum.
- An at-fault claim usually steps the bonus back several years or resets it.
- Protected no-claims bonus preserves the discount after limited claims, for an extra premium.
- Bonus schedules vary by insurer and market, so always use your own figures.
- The base premium can change at renewal independently of the bonus.
No-claims bonus: frequently asked questions
What is a no-claims bonus?
A no-claims bonus (NCB), also called a no-claims discount, is a reduction in your insurance premium earned by going a policy year without a claim. The discount grows with each consecutive claim-free year up to a maximum set by the insurer, rewarding lower-risk policyholders.
How is the discounted premium calculated?
Discounted premium = base premium times (1 minus the discount percentage). The dollar saving is the base premium minus the discounted premium, which equals base premium times the discount percentage. This calculator applies your own base premium and discount rate, so nothing is assumed.
Where does the discount percentage come from?
It comes from your insurer's no-claims bonus schedule, which varies by company, market, and number of claim-free years. Because there is no universal scale, the current and next-year discount percentages are user-editable inputs here.
What happens to my bonus if I make a claim?
Most insurers reduce or reset the no-claims bonus after an at-fault claim, often stepping it back several years. Some offer protected no-claims bonus for an extra premium that preserves the discount after a limited number of claims. Check your policy wording for the exact step-back rule.
What is the next-year preview?
It shows the premium and saving you would receive after another claim-free year, using the next bonus level's discount percentage that you enter. It helps you see the value of staying claim-free, though the base premium itself may also change at renewal.
Official sources
- National Association of Insurance Commissioners: NAIC auto insurance consumer information.
- U.S. Internal Revenue Service: IRS guidance on insurance premiums and deductions.
Reviewed by the CalculatorHub team, edited by James Graham, 17 June 2026. See our methodology.