Warranty Reserve Calculator
The warranty cost to expect per unit sold — from the failure rate within the warranty period, the cost of a claim and the cost of handling it — and the total provision and its share of revenue.
A share of units will fail inside the warranty period; each failure costs a repair or replacement plus the freight, labour and administration of handling the claim.
How the warranty reserve calculator works
A share of units will fail inside the warranty period; each failure costs a repair or replacement plus the freight, labour and administration of handling the claim. Failure rate × cost per claim is the expected cost per unit sold, which accounting sets aside as a provision at the time of sale. Multiply by units for the reserve, and compare with the price to see what warranty costs as a share of revenue — typically 1–3% for consumer goods.
Formula: per unit = failure rate × (claim cost + handling cost); reserve = per unit × units sold
Worked examples
| Inputs | Warranty reserve for the period | Note |
|---|---|---|
| 20,000 units, 2.5% failures, 90 + 25 per claim | 57,500 | 57,500 — 2.88 per unit, 1.15% of revenue |
| A reliable product: 0.8% | 16,800 | 16,800 — 0.84% of revenue |
| A troubled product: 8% | 116,000 | 116,000 — 3.9% of revenue |
FAQFrequently asked questions
How do I estimate the failure rate?
From claims history on similar products — claims in the warranty period divided by units sold in the matching period — or from reliability testing and supplier data for a new product. Rates run from under 1% for simple goods to 5–10% for complex electronics.
Why include handling?
Because a claim costs more than the part: freight both ways, call-centre time, inspection, and sometimes a replacement shipped before the failed unit returns. Handling often exceeds the repair cost on cheap items.
Is the reserve a cash account?
Usually an accounting provision — a liability recognised at the sale so that the cost sits in the same period as the revenue. Cash goes out as claims arrive, over the warranty period.
How does an extended warranty differ?
It is sold separately and priced from the same arithmetic plus margin; the failure rate over the longer period is higher, and so is the claim cost as the product ages.
Where these figures come from
- Corporate Finance Institute — EBITDA — why EBITDA is a non-GAAP measure with no single definition
- US SEC — Non-GAAP Financial Measures, Compliance & Disclosure Interpretations — the disclosure rules that exist precisely because EBITDA is not standardised
- Financial Reporting Council — the UK accounting and audit regulator
Last checked: September 2026. These are standard management-accounting definitions; where a term has no single agreed definition, the page says so.