Shopify POS and Klaviyo: Turn In-Store Buyers into Repeat Customers

By Trayan Hristov · Thrivelia · 21 October 2026

Someone buys a jacket in your shop, then receives an email introducing the brand as if they have never purchased. Later they buy online and appear to be a new customer again. The issue is the relationship between identity, order history and the messages each system sends.

A useful retail email programme recognises customers across store and online purchases where reliable identification exists. It then changes the follow-up to reflect what they own, where they bought and what would help them next.

Start with identity and channel eligibility

Trace a store purchase from the till to Shopify and then into Klaviyo. Confirm which customer profile receives it, which identifiers are present and whether the profile carries the appropriate channel status. Record what happens when an order has no usable customer identifier.

Shopify's customer management documentation describes customer profiles and profile merging. Establish a reviewed process for possible duplicates. A matching name or an assumption that two shoppers live together is not sufficient evidence that they are the same person.

Keep a receipt request and marketing preferences distinct in the operating process. Have the responsible team verify eligibility before adding customers to promotional journeys. Accurate purchase history and permission to receive a particular message are separate fields to check.

Distinguish the order source from the whole customer

Klaviyo's Shopify POS and web data guide explains that the order's source_name appears as Source Name in segment and flow filters. The value pos identifies POS orders, while web identifies web orders.

Use that information to answer two different questions. Where did this particular order happen? And has this identified customer bought through more than one source? A person can belong to both the POS and web customer groups. Do not add the two group totals and assume they represent unique customers.

A segment of people who have ever placed a POS order is also different from a flow responding to a particular new POS purchase. In the second case, verify the triggering order's source. Otherwise, an online order from an established store customer can enter the wrong follow-up.

Build four useful customer groups

• Identified store buyers with no observed web purchase: consider useful product support and a clear route to shop online.

• Identified web buyers with no observed store purchase: offer store information only where location and customer context make it relevant.

• Buyers observed in both sources: recognise the combined purchase history and avoid treating one source as the entire relationship.

• Orders or profiles with unresolved identity: improve data quality before making confident personalisation claims.

Make the observation period explicit. “No observed web purchase in the available data” is a defensible definition. “Never shops online” makes a broader claim than the records can usually support.

Design the first follow-up around the purchase

A shop buyer may already have tried on the garment and discussed fit with a member of staff. They may need care advice, styling ideas or help finding a complementary item. Sending the same first-purchase discount introduction used for a new lead can make the programme feel disconnected.

An illustrative first follow-up for a fictional fashion retailer could thank the customer for the jacket purchase, explain its care requirements and link to a useful styling page. Where the integration reliably supplies the store and product, those details can improve the message. Use a neutral fallback when they are missing.

Delivery-based timing should reflect the transaction. A product taken home from a store does not need the same wait as an online order being shipped. A POS order arranged for later delivery needs a different handoff again. Verify fulfilment rather than treating all pos orders as immediately received.

An annotated store-to-online email example

This is fictional copy for a customer whose identified POS purchase and promotional eligibility have been checked.

Subject: Three ways to wear your new jacket Thanks for visiting us. We have put together three styling ideas for the jacket you chose, with details on the layers that work with it. You can browse those pieces online whenever it suits you. Button: Explore the styling ideas

The opening acknowledges the store relationship. The body helps the customer use something they already own. The destination introduces online shopping through a practical reason, rather than requiring another discount to justify the message.

The pictured combinations must be real, available and appropriate to that jacket. If you do not have a useful styling page, create one or choose a simpler care message. A generic collection link does not become personalised simply because the email names the purchased product.

Give store and ecommerce teams a shared brief

Agree what information staff should capture, how customers express preferences and who maintains product advice. Ask store colleagues which questions repeat after purchase. Those questions can become care content, comparison guidance or a better fit explanation for email.

Also agree which team owns a support conversation when someone buys in one source and asks for help through another. The customer should not have to understand the internal reporting structure to receive a coherent answer.

For the wider merchandising approach, use our fashion and apparel lifecycle guide. For product progression after the first order, see choosing the next cross-sell product.

Measure the relationship across both sources

Define a cohort of identified first-time store buyers, then give every customer the same observation window. Track a genuine second purchase anywhere in the observed business, alongside the narrower measure of a first subsequent web purchase. They answer different questions.

For example, 1,000 eligible store buyers might produce 120 genuine second purchases within a complete 90-day window: 80 in store and 40 online. The observed second-purchase rate is 12%; the store-to-web rate is 4%. These are illustrative numbers. Counting only web purchases would miss most of the observed repeat activity.

To test an additional marketing journey, compare suitable eligible customers receiving the treatment with a control where feasible, while keeping service messages consistent. Review net retained sales and messaging costs as well as the purchase rate. The fact that a store customer later bought online does not, by itself, prove that email caused the purchase.

A release checklist for retail teams

• Test an identified POS order, an unidentified order and an online order from an existing POS customer.

• Check that the triggering order source and lifetime purchase history serve their intended roles.

• Verify how purchase, fulfilment and current marketing eligibility reach Klaviyo.

• Inspect duplicate-profile handling with a reviewed test record.

• Confirm that online and store repeat purchases appear in the customer analysis.

• Open the delivered message, product page and support route on mobile.

Questions teams ask

Does a POS segment identify every customer who shops in store?

It identifies the people connected to the observed POS events that meet your definition. Unidentified transactions and unresolved profiles create gaps. Report those limitations alongside the identified cohort.

Should store buyers receive a separate welcome flow?

They may benefit from a different purchase-aware introduction. Decide what they still need to know, then check existing flows so they do not receive competing new-lead and customer messages.

Turn the map into a working journey

Thrivelia's Klaviyo agency service covers account diagnosis, journey planning and implementation. For retail fashion, our fashion email marketing service connects the merchandising brief with the customer journey. Begin with one store transaction and verify the full path before expanding the programme.