How Do I Write a Warranty for My Small Business?

By Bill Stilwell · Last reviewed October 17, 2026

The short answer

A warranty is your written promise about what you’ll fix, replace, or refund, for how long, and under what conditions. Federal law doesn’t make you offer a written warranty. If you do offer one on a consumer product, the federal Magnuson-Moss Warranty Act sets rules for what it must say and when customers must be able to see it.

What this means

11.1.9 Service warranty

Most service businesses offer a workmanship warranty. It promises that the work was done right and that you’ll fix problems caused by your work for a set time.

A good service warranty says:

What is covered (your labor, your installation, parts you supplied)
How long it lasts, and when the clock starts
What isn’t covered (misuse, normal wear, damage from others, parts the customer supplied)
What you’ll do (repair, redo, or refund)
How to make a claim

Made-up example: Summit Roofing gives a 5-year workmanship warranty on new roofs, starting on the completion date. It covers leaks caused by installation. It doesn’t cover storm damage or shingle defects, which fall under the manufacturer’s warranty. The warranty is a one-page document handed over with the final invoice.

26.2.6 Product warranty

If you sell physical products to consumers, federal rules apply once you offer a written warranty. According to the Federal Trade Commission (FTC):

The law covers consumer products, meaning things normally used for personal, family, or household purposes. It generally doesn’t cover services, but it does apply when a warranty covers both parts and workmanship in a repair.
Products over $10 with a written warranty must label it “full” or “limited.” A full warranty must meet five conditions, including free service and a choice of replacement or refund if repairs don’t work. If any condition isn’t met, it’s limited.
Products over $15 need the warranty terms in one clear, easy-to-read document, and buyers must be able to see the warranty before they buy.
Tie-ins are generally banned. You can’t make coverage depend on the buyer using a specific brand of parts or service, with narrow exceptions.

Implied warranties. State law also gives buyers “implied warranties,” like the basic promise that a product works for its normal purpose. If you sell without a written warranty, most states let you disclaim these with a clear “as is” notice. If you give a written warranty, you can’t disclaim implied warranties, though a limited warranty can limit how long they last.

Why it matters

Vague warranties cause fights. “We stand behind our work” doesn’t say for how long or for what.
Federal rules apply to product warranties. Missing labels or hidden terms can break the law.
Warranty claims cost money. You need to plan for them (see 7.8.7 Warranty, Refund, and Bad Debt Costs).
A promise in an ad is a promise. The FTC says ads that mention a warranty should tell customers how to get the details.

Who this applies to

Every business that promises anything about how long its work or product will last. Pure advice or one-time services with nothing to fail can skip a formal warranty, but should say so in the agreement.

How to do it

Decide what you will stand behind and for how long. Base it on what you can afford to fix.
Separate your warranty from the manufacturer’s. Tell customers which one covers what.
Write the exclusions in plain words.
Explain how to make a claim: who to call, what proof to send, and how fast you respond.
For consumer products, follow the FTC rules: label it full or limited, put terms in one document, and make it available before the sale.
Give it to the customer in writing, with the invoice or the product.
Make your ads match. If your website says “lifetime warranty,” the document must say the same (see 11.3.1 Truthful Advertising Claims).
Track claims. Repeat claims point to a training or quality problem (see 17.7 Quality Control).

What proof to keep

The warranty document, with version dates
Proof it was given to each customer (signed agreement or invoice)
Manufacturer warranty papers for parts you installed
A log of warranty claims, what you did, and the cost

Common mistakes

Calling it a “full” warranty when it charges for labor or limits who can claim it.
Promising “lifetime” coverage without saying whose lifetime: the product, the buyer, or the company.
Not telling customers the manufacturer’s warranty exists. They call you for a part defect you can’t fix for free.
Requiring your own parts or service to keep coverage. That’s generally a banned tie-in for consumer products.
Saying “as is” while also giving a written warranty. You can’t disclaim implied warranties once you give a written one.

When to get help from a pro

Attorney: to review your warranty language. Questions to ask:

Does the Magnuson-Moss Warranty Act apply to what I sell?
How do implied warranties work in my state?
How should my warranty interact with manufacturer warranties?

Bill’s note

[Bill: add a short note. For example, what SiteSmarty promises after a website launch, like a bug-fix window, or a business owner whose clear warranty turned a callback into a five-star review.]

How I did this for SiteSmarty

[Date I did this:]
[What I actually did, step by step: what SiteSmarty covers after delivery and for how long]
[What it cost and how long it took:]
[What surprised me or what I’d do differently:]
[Screenshot or photo to add, with private info blurred: the warranty section of the SiteSmarty agreement]
[Result so far:]

Questions people ask

Do I have to offer a warranty? No. Federal law doesn’t require a written warranty. State implied warranties may still apply unless you disclaim them properly.

What is the difference between full and limited? A full warranty meets five federal conditions, including free service. Anything less is limited.

Can I sell “as is”? In most states, yes, if you don’t give a written warranty and the “as is” notice is clear. The FTC notes it doesn’t remove liability for injuries.

Does the federal warranty law cover my service business? Generally not for pure services. It can apply when you warrant both parts and workmanship on a repair.

Audit check

Line	Question	Pass looks like	Fail looks like	Evidence to collect
11.1.9 Warranty	Is there a written warranty stating coverage, length, conditions, and claim steps?	One clear document given to every customer	Verbal promises, vague “we stand behind it”	Warranty document and signed agreements
26.2.6 Product warranty	Do product warranties follow federal labeling and pre-sale rules?	Labeled full or limited, one document, available before purchase	No label, hidden terms, tie-in requirements	Product listings, warranty copies, store displays

Where this fits

Do this first: 11.1.1 Service Agreement, 11.1.8 Refund Policy

Do this next: 11.1.10 Privacy Notice

Sources

Federal Trade Commission, "Businessperson's Guide to Federal Warranty Law" (checked October 17, 2026)
Federal Trade Commission, "Advertising FAQ's: A Guide for Small Business" (checked October 17, 2026)
Google Business Profile Help, "Tips to improve your local ranking on Google" (checked October 17, 2026)

This page explains general rules and Bill's own experience. It is not legal, tax, or insurance advice. Talk to a qualified professional about your situation.