AI-Powered Welcome Pop-Up: 15.5% of Store Revenue and 3× Sign-Ups

The Client

A premium baby and kids' clothing brand selling online. Its customers fall into two groups: parents buying for their own children, and people buying a gift for someone else's baby or child, from new arrivals to birthdays. The welcome pop-up is the main way new visitors join the email list and receive a first-order offer.

The Challenge

When we took over the account, the pop-up we inherited was losing both sign-ups and sales. It ran as two separate Klaviyo forms, one for mobile and one for desktop, offering a small fixed discount with no minimum spend. After signing up, shoppers were told to check their inbox for the code.

• Sign-ups were falling. Outside sale weeks it averaged a 3.5% sign-up rate, and mobile, where most of the traffic was, fell from 3.97% in early May to 1.37% by late July.
• Sales from the code were falling too. Monthly sales from orders using the pop-up's code nearly halved between January and June. By June, those orders made up just 7% of store orders and 7% of store revenue, down from 14% of orders in January. And because the code only arrived by email, almost none of those sales came straight from the pop-up: about 1% of store revenue.

There was a second, hidden problem: nobody could say what the pop-up was worth on its own. The form dashboard showed sign-ups and the revenue Klaviyo attributed to them, and the welcome flow was credited with orders from people who had opened or clicked an email. The two reports overlap, and neither separates the sales the pop-up drove by itself from the ones the welcome emails drove.

The Solution

We rebuilt the pop-up as a sales tool, not just a sign-up form: a stronger offer, a discount code the shopper can use the moment they sign up, and a way to measure exactly how many sales it drives. Once the results showed what it could do, we moved it to Alia to push it further. Claude, connected to Klaviyo and Shopify through MCP, worked alongside us at every stage.

Rebuilt the pop-up in Klaviyo around four changes. Together they took the sign-up rate from 3.5% to 7.0% and turned the pop-up into a sales channel.

1. One multi-step form replaced the separate mobile and desktop forms.
2. A much stronger offer. The small no-minimum discount became a far more valuable first-order offer with a minimum spend.
3. Zero-party data. The first step asks one question, "Who are you shopping for?", and saves the answer to the subscriber's profile before the email step.
4. The code on the success screen. Each shopper gets their own unique, single-use code, shown straight away with a copy button and a Start Shopping button, so they can buy without waiting for the email. The original pop-up only told them to check their inbox.

• Tested a fixed-dollar offer against a percentage offer, both with the same minimum spend and expiry. Before launch, we used Claude to model both against 90 days of orders so the two cost almost exactly the same at the typical basket. The test measured how shoppers reacted to the framing, not to a bigger discount. The fixed-dollar version won with a 10.1% sign-up rate against 7.9%, 29% higher, and became the only offer after the first week.
• Found that the pop-up sells in the first hour. Of all orders placed with the welcome code within a week of signing up, 55% came in the first hour. With the code right there on screen, the pop-up was not just collecting emails for later; it was closing sales on the spot.
• Moved the pop-up to Alia to push it further. Alia kept the code on the success screen and added more control: the pop-up shows only to new visitors, smart triggering decides when it appears, and customers Alia recognises as past buyers are screened out, so the first-order offer goes to first-time customers. That screening was something we struggled to set up reliably in Klaviyo.
• Built an attribution method the dashboards cannot match. Every pop-up code is unique to one sign-up, so every redemption is a confirmed pop-up order. Every month we count them all, then use Claude to check each one against the customer's Klaviyo email activity. If they opened or clicked a welcome email before ordering, the sale belongs to the welcome flow; if not, it belongs to the pop-up.
• Used Claude as builder and analyst throughout. With Claude connected to Klaviyo and Shopify through MCP, we built the form logic, profile properties, welcome flow wiring and code tags in every email, set the before-and-after conversion baselines on matched weeks without a sale, read the offer test, ran the sign-up-to-order analysis that found the first-hour pattern, and checked the form set-up before launch.

The Results

Sales

• Pop-up sales grew 2.5×. Monthly sales from orders using the pop-up's code in September were 2.5× the old pop-up's monthly average for January to June.
• Orders straight from the pop-up grew almost 7×, compared with the old pop-up's monthly average.
• Sales straight from the pop-up grew about 10×, from about 1% to 15.5% of store revenue. These are orders using the pop-up's code where the shopper had not opened a welcome email first. The old pop-up only sent the code by email, so almost none of its sales came this way.
• Most of these sales bypass the email reports. Klaviyo only credits an order to email if an email was opened or clicked first. In August and September, 58–62% of orders using the pop-up's code came straight from the pop-up, sales that would never have appeared in a standard email report.

Sign-ups

• 231% more pop-up sign-ups a week after the rebuild, comparing weeks without a sale.
• Sign-up rate doubled, from 3.5% to 7.0%, while about two-thirds more visitors saw the pop-up each week.
• New email subscribers per month nearly tripled in the first full month after the rebuild.
• Alia took it further, to an 11% sign-up rate, more than 3× the original pop-up's 3.5%: in its first three weeks it brought in about 30% more sign-ups than the rebuilt Klaviyo pop-up, and more than 4× the original.

Key Takeaway

A welcome pop-up's first job is building the list, and the rebuild more than tripled its sign-ups. Some of those shoppers arrived ready to buy anyway; the difference is that they no longer had to wait for an email to get their code. With the code on screen, more than half of code orders now happen within an hour of signing up, and sales straight from the pop-up grew about 10×, from about 1% to 15.5% of store revenue. Platform dashboards cannot separate this from the welcome emails, because each only sees its own part of the journey. Counting every code redemption and matching it to email history with Claude turned the pop-up into a channel we measure month by month.

The next step is taking the same idea beyond new subscribers: pop-ups with their own offer and message for repeat customers, customers who have gone quiet, loyalty members, and other key segments.

Kinga Dow specializes in building retention marketing with Claude: knowing how to lead it, what to ask of it, and how to turn new AI capabilities into exceptional results for e-commerce brands.