What to Ask Before You Sign an AI-Driven Conversion Lift Guarantee

An AI-driven conversion lift guarantee sounds like a no-risk way to grow revenue. But guarantees only protect you if the contract is precise about what is measured, how it is measured, and what happens when results fall short. Start with these ten questions, then read on for the details that turn a vague promise into a useful commitment.

The ten questions to ask before signing

1. What is the baseline? Is it your current conversion rate, a rolling average, or a period you select? A weak baseline can make a lift look real when it isn't.
2. How do you define a 'conversion'? Is it a sale, a lead, a demo, or something else? The definition drives every number.
3. What is the exact measurement method? Randomised tests, before-and-after, or a model? A controlled test is more trustworthy than a simple trend.
4. How is the lift calculated? Relative or absolute percentage? A 10% relative lift is different from a 10-point absolute lift.
5. What data do you need from us? Will you require access to analytics, server logs, or customer data? How is that data secured?
6. What happens if you don't meet the target? Is there a refund, credits, or an extended trial? What are the exact terms?
7. How long is the guarantee period? Is it 30 days, 90 days, or a year? When does the clock start?
8. Are there exclusions? Do certain traffic sources, campaigns, or page types fall outside the guarantee?
9. Can you share a case study with a similar client? Check that the case study uses the same measurement method and shows the full history, not just a cherry-picked month.
10. What are the exit clauses? Can you cancel at any time, or is there a lock-in? What notice is required?

Why the guarantee wording matters

A guarantee is only as strong as the contract that backs it. Vague language like 'we'll improve conversions' leaves room for interpretation. For example, a vendor might report a 'lift' based on a change in the conversion rate from 2% to 2.2%, which is a 10% relative lift, but that could be statistically meaningless with low traffic. Ask for the exact formula and the minimum sample size.

If the vendor claims an average lift across clients, find out how many clients and how they account for seasonality or campaign changes. An average can hide wide variations. One client might see +60%, another +5%. And without a control group, you can't tell if the lift came from the AI or from a sudden demand spike.

How to define a 'conversion' and a 'lift'

Start with your own business goal. Is the guarantee tied to revenue, leads, or sign-ups? The vendor's definition may not match yours. For example, an AI agent might optimise for 'click-to-call' events, but you care about qualified demos. Make sure the contract names the exact event and that event matters to your bottom line.

The 'lift' itself needs a denominator. Is it conversions per visitor, per click, or per session? And is the lift measured against your baseline before the AI was deployed, or against a control group during the same period? A same-period control group is stronger because it cancels out seasonality, ad budget changes, and competitor moves.

Measurement methodology: what exactly counts?

Most reputable vendors will use a randomised A/B test or a holdout group. If the vendor says they 'observed a lift' after turning on the AI, ask how they know the AI caused it. Good signs include:

• A pre-registered test that defines the metric and the significance threshold.
• At least 80% statistical power or a stated confidence level.
• An independent third-party verification or at least an audit trail.
• Clear handling of outliers and ad fraud.

If the vendor can't explain the methodology in plain language, that's a red flag. You don't need to be a statistician, but you should be able to understand how they will prove the result.

Remedies and payouts: what happens if the lift doesn't happen

Ask what you receive if the guarantee fails. Common structures are:

• Full refund of fees paid during the period.
• Credits for future months.
• Extended service at no additional cost.
• A prorated refund based on the shortfall.

Watch for remedies that are hard to enforce. A vendor might promise 'we'll work with you to improve', which is not a remedy. The contract should state a clear, objective payout trigger. Also check whether the guarantee covers all fees or only the AI software fee, excluding onboarding or test setup costs.

Example from the source pack: SeaText advertises an average +35% conversion lift across clients (source S3). If you signed a guarantee like that, you'd want to know exactly how that average is calculated and what a 'client' means. Does it include every client, or only the best performers? The contract should specify the calculation.

Data access and transparency requirements

Many AI conversion platforms need to read your website, ads, and sometimes customer data to personalise pages. Before signing, ask:

• What data does the AI see? (e.g., search queries, visitor behaviour, transaction history)
• Is that data shared with third parties?
• How long is the data stored?
• Can you export your own data at any time?
• What happens to the AI's learnings if you cancel? Do you keep the 'optimised' copies?

You also want control. Some platforms let you approve changes before they go live. If the guarantee depends on the AI making autonomous changes, you need to know whether you can veto those changes without invalidating the guarantee. That's a fair trade-off: you get protection only if you grant the necessary access.

Case studies and proof: what to look for

Ask for written case studies that show the setup, the baseline, the intervention, and the measured lift. Avoid ones that only show a before-and-after number with no context. Good case studies include:

• The exact conversion event and how it was tracked.
• The traffic volume and duration of the test.
• The statistical significance level.
• The time period compared.

If the vendor says 'trusted by 2,500+ brands' (source S4), that doesn't tell you if they're relevant to your situation. Ask for case studies in your industry and of similar size. If they only have examples from ecommerce but you run a B2B SaaS, ask how the approach changes.

Also look for independent reviews or audits. A vendor's own reporting can be biased. The more third-party evidence they can share, the more likely the guarantee is genuine.

Contract terms: duration, exit clauses, and testing

How long does the guarantee run? If it's a 6-month contract, is the guarantee assessed monthly or quarterly? What if you change your ad spend or product mid-period? The vendor may argue that external changes invalidate the guarantee. Make sure the contract specifies how major changes affect the measurement.

Exit clauses matter too. Can you terminate after 30 days if the AI is hurting more than helping? What is the notice period? Some contracts lock you in for a year, but the guarantee only covers the first 3 months. That's a trap. Check that the guarantee period aligns with the contract length.

Also ask about testing. Does the vendor allow you to run your own A/B tests to verify their lift independently? If they block that, you may never know if the AI is the true cause.

Key facts from SeaText (source pack)

Common mistakes to avoid

Not defining your own conversion metric. If you don't know what you want to improve, you can't evaluate the guarantee. Suppose you ask for 'more leads' but the vendor counts any form submission, including spam. You'll end up paying for junk.

Ignoring the baseline. A vendor can cherry-pick a bad baseline to make their lift look bigger. If your conversion rate was unusually low during the measurement period, you'll see an 'improvement' that's not sustainable.

Trusting a single number. An 'average lift of 35%' is meaningless without distribution. Ask for the median, the range, and the standard deviation.

Assuming the guarantee covers all traffic. If you run ads on Google, Meta, and TikTok, confirm the guarantee applies to all of them. Some vendors only measure Google Ads and exclude others.

Signing before you see the contract. Get the written guarantee terms before you sign the service agreement. If the vendor won't share a draft, that's a red flag.

FAQ

What is a conversion lift guarantee?

It's a contractual promise that a software vendor will improve a specified conversion metric by a defined amount over a baseline. If they don't, you receive a remedy like a refund or credits.

How is the lift typically measured?

Usually with a controlled test: a portion of traffic sees the AI-personalised pages and another doesn't. The difference in conversion rates between the two groups is the lift. Some vendors use a before-and-after comparison, but that's less reliable.

What should I ask about the baseline?

Ask for the exact period, the calculation method (e.g., 30-day rolling average), and whether you can approve the baseline before the test starts. Also ask how they handle seasonal spikes or dips.

Are there any hidden costs in a conversion lift guarantee?

Check for onboarding fees, setup costs, or minimum spend requirements. The payout might be based on net fees after deductions, or you might need to maintain a certain ad budget to qualify.

Can I cancel if the vendor doesn't meet the guarantee?

Only if the contract says so. Some vendors offer a refund but still require you to complete the full term. Read the exit clause carefully.

How long does it take to see a lift?

It depends on traffic volume and the nature of changes. For low-traffic sites, it could take months to reach statistical significance. Ask for an estimated timeline and what happens if the test is inconclusive — does the guarantee extend?