THIS ARTICLE IS FOR: All ListKit customers and anyone running cold email
Stage: Optimization
Owner: CS
Last updated: Aug 2026
TL;DR
A guarantee dramatically increases how many cold prospects will engage with your offer, often by several multiples
The less evidence you have, the more a guarantee is doing the work of convincing someone to take a chance on you
Guarantees only work safely when they come with clear stipulations, conditions the client must meet to stay eligible
If you do not have a written refund policy, most payment providers will side with the client in a dispute by default
A well-structured guarantee with reasonable stipulations should produce a very low refund rate, not a high one
Why this matters / When you'd use this
Once your claim is in place (see: How do I write a claim that gets replies?), the next question a prospect asks, consciously or not, is: what happens if this doesn't work for me? A guarantee answers that question before they have to ask it, and it is one of the biggest levers you can pull to increase how many cold prospects actually respond and book a call.
The reason a lot of people avoid guarantees is fear of getting stuck refunding clients who did not put in the work. This article covers how to guarantee results without exposing yourself to that risk.
Why a guarantee matters so much in cold email
A stranger reading a cold email has no reason to trust you yet. They have no relationship with you, no history, and usually no other signal to go on besides what you tell them. A guarantee removes a large part of the risk of trying you out, which is often the single biggest thing standing between a prospect and a reply.
The less evidence you have to back up your claim, the more weight the guarantee has to carry. If you have almost no case studies yet, a strong guarantee is often what makes people willing to take a chance on you at all.
Types of guarantees, from lowest to highest risk to you
Performance basis: the client only pays after the result happens. There is no risk to them at all, which makes this the easiest guarantee to sell, but it also means your own cash flow depends entirely on results landing.
Implicit guarantee: the client pays as results happen, in stages tied to specific outcomes. Still very low risk to the client.
Money-back guarantee: the client pays upfront and gets refunded if the result is not achieved. This carries the most apparent risk to the client, which is exactly why it needs the most careful structuring on your end.
The part most people get wrong: stipulations
A guarantee without stipulations is a guarantee you should never make. Stipulations are the specific things the client is required to do or already have in order to remain eligible for the guarantee.
There are two kinds:
Things the client must already have: for example, an active social media account in good standing, or a minimum website traffic level.
Things the client must actively do: for example, posting content on schedule, responding to a minimum percentage of comments, staying current on payments, or following the process you provide.
The goal of stipulations is simple: design the guarantee so the only way the result fails to happen is if it is genuinely your fault, not theirs. If a client stops doing their part of the process, they should no longer be eligible for a refund, and that needs to be written down clearly before they sign, not negotiated after something goes wrong.
Do not sign clients you cannot actually deliver for
A guarantee only stays healthy if you are disciplined about who you offer it to. If a conversation with a prospect makes it clear you cannot realistically achieve the result for their specific situation, do not offer them that guarantee, offer a different, more realistic outcome instead, or decline to guarantee anything for that particular deal.
This is a negotiation, not a fixed script. You are not obligated to offer the exact same guarantee to every single prospect who gets on a call with you.
Why having no written guarantee is riskier than having one
If you do not have a clearly written refund policy, most payment providers default to assuming the client can request a refund for any reason if a dispute is opened. In other words, skipping a guarantee does not actually protect you, it just means you have no defined terms to point to when something goes wrong.
A clearly written guarantee, with clear stipulations, gives you something concrete to stand on if a client tries to claim a refund they are not entitled to.
Expected outcome
A properly structured guarantee, matched to your evidence level, with clear stipulations spelled out before the client signs, should noticeably increase how many cold prospects convert into calls and clients, while keeping your actual refund rate low. The guarantee should be doing the work of getting attention, not creating ongoing liability.
Frequently asked questions
Do I need a guarantee if I already have strong case studies?
Not necessarily. As your evidence grows, it can carry more of the weight that a guarantee would otherwise carry. Many offers with extensive, well-documented results can convert well with little or no guarantee attached.
What if a client ignores the stipulations and then asks for a refund?
This is exactly what the stipulations are for. If they are written clearly and the client did not meet them, you are within your rights to decline the refund, which is why they need to be in writing before the client signs, not discussed informally.
Will offering a guarantee attract clients who are more likely to ask for refunds?
It can increase the volume of people willing to try you, which makes qualifying prospects properly even more important. A guarantee should never be offered blindly to everyone who reaches out.