No Claim Bonus in Health Insurance 2026: How Much a Single Small Claim Actually Costs You

By Nitish Bharadwaj · Published Sep 8, 2026 · 6 min

Since IRDAI's October 2020 standardization guidelines, health insurers cannot reset an accumulated Cumulative Bonus (No Claim Bonus) to zero after a single claim — it must reduce at the same rate it accrued, and the total sum insured can never fall below the original base amount. This guide walks through the real math on a claim-free bonus build-up versus a mid-way claim, when a 'Cumulative Bonus Protector' add-on is worth its extra premium, and why avoiding a genuine claim to protect a bonus is usually the costlier decision.

Health insurance folklore has one rule almost every policyholder repeats with total confidence: file a claim, even a small one, and you lose your entire accumulated No Claim Bonus overnight. It's a myth with just enough truth in its history to keep spreading — some older, pre-2020 policy wordings genuinely worked that way. Since IRDAI standardized the rule in October 2020, a claim reduces your bonus at the exact rate it built up, not to zero, and your sum insured can never drop below what you started with. Here's what a single small claim actually costs you, in real numbers.

How the Cumulative Bonus (No Claim Bonus) Actually Builds Up

The Cumulative Bonus — what most people call the No Claim Bonus, or NCB — increases your health insurance sum insured by a fixed percentage for every year you go without filing a claim, at no extra premium. The accrual rate and cap vary by insurer and plan: many mainstream retail policies add 5-10% per claim-free year up to a 50-100% cap, while some newer plans front-load a larger jump — up to 50% after the very first claim-free year — before slowing down. Either way, the mechanism is the same: it's an increase to your cover, not a discount on your premium, which is how car insurance NCB works instead.

The 2020 Rule Change: Reduction, Not Reset

IRDAI's Guidelines on Standardization of General Terms and Clauses in Health Insurance, effective from October 1, 2020, rewrote how insurers are allowed to word this clause. The standardized language most insurers now carry states that if a claim is made in a policy year, the Cumulative Bonus accrued shall be reduced at the same rate at which it accrued — and the total sum insured, even after that reduction, cannot fall below the original base sum insured you started with. A claim shrinks the bonus proportionally to how it grew; it doesn't zero it out, and it can't push your cover below day one.

The Real Math: What a Small Claim Actually Costs

Take a ₹10 lakh base policy that has run claim-free for four years, accruing 10% a year, bringing the sum insured to ₹14 lakh (a 40% bonus). A policyholder files one claim of ₹15,000 in year five for a minor procedure. Under the old, popularly-assumed logic, the entire 40% bonus would vanish, dropping cover straight back to the ₹10 lakh base — a ₹4 lakh loss in cover to avoid paying ₹15,000 out of pocket. Under the actual, current IRDAI-mandated rule, the bonus reduces by one year's worth of accrual — 10 percentage points — bringing it down to a 30% bonus, or ₹13 lakh in cover. The real cost of that claim is ₹1 lakh in reduced future cover, not ₹4 lakh.

When Filing the Claim Is Still the Right Call

Policyholders who delay or skip a genuine claim purely to protect an accumulated bonus are usually making the trade in the wrong direction — paying a real hospital bill out of pocket today to protect a hypothetical ₹1-4 lakh of extra cover that may never even get used. The bonus only matters if a future claim is large enough to exceed the base sum insured; for most policyholders, the base cover itself, not the accumulated bonus on top of it, is what a serious hospitalisation draws down first. Our guide on No Claim Bonus vs restoration benefit covers the related feature that actually protects you within a bad claim year, which matters more than bonus preservation when a large hospitalisation is involved.

None of this changes the incentive to actually avoid unnecessary claims — every claim still affects your policy's claims history, and insurers do factor claims frequency into renewal terms and portability decisions over time. But the specific fear that a single small claim wipes out years of bonus growth overnight is outdated for any policy carrying the post-2020 standardized wording, and it shouldn't be the reason a genuine, medically necessary claim goes unfiled. Before relying on any insurer's specific numbers, check your own policy document's Cumulative Bonus clause directly — the accrual rate, the cap, and the exact reduction language can still differ from one product to the next even under the same regulatory floor.