Duplicate Customers from Shopify POS: Causes and Cleanup

Shopify POS creates duplicate customers when it makes a new profile for someone who already has one, and at a counter there are three ways that happens: a cashier adds the customer without finding their existing profile, the customer creates one by choosing an email or text receipt with a different contact than they use online, or POS creates a name-only profile automatically from an inserted chip card. None of these check for a likely match under other details. You can cut the flow with search habits and the POS Pro checkout settings, then find and merge what's left in the Shopify admin.

This guide goes through each source, what Shopify's documentation says about it, and a cleanup routine built for stores that sell both in person and online.

How does Shopify POS create customer profiles?

Shopify POS creates profiles in three ways: staff create them, customers create them at checkout, and some are created automatically when a customer pays with a card. Each path adds a profile to the same customer list your online store uses.

According to Shopify's POS help pages, a profile can hold a first and last name, email, phone number, notes, shipping addresses, marketing preference, tax-exempt status and tags. Staff need very little to save one: the creation steps ask for a first name, last name, email or phone number. That is convenient at a busy register and is exactly why POS produces thin profiles that are hard to match later.

Why does POS create name-only customer profiles?

Because Shopify POS creates a profile automatically when a chip card is inserted and the card network shares the cardholder's first and last name. No staff action is involved, and the profile holds only that name.

Shopify's documentation is specific about the limits. Contactless (tapped) cards don't share a name, so they create no profile. The automatic profile shows up on the Customers page in your admin, and to add an email or phone you edit it in POS or the admin. Card names depend on the bank: on the Shopify Community, a merchant asking why card names appeared on in-store orders was told by support that it comes from the cardholder's bank and isn't something the merchant can switch off.

These profiles are the hardest POS duplicates to deal with. A customer who has bought online for two years as jane@example.com, then inserts her card at your pop-up, gets a second profile called "Jane Doe" with no email, no phone and no address. Nothing on it points back to her online profile except the name, and names alone are a weak match.

Shopify POS can also recognize a returning card, with Shopify Payments and POS version 11.17 or later. If the card is already linked to a customer, that customer is added to the new order automatically. If the card was used before but isn't linked, an Add customer option appears under More actions with the note "This is a repeat customer." Adding the customer links the card to that profile, which is useful, but it also means the choice matters: in a 2022 Community thread, a merchant reported a customer's card linked to the wrong profile, so later purchases kept landing there, and the thread ended with a referral to retail support rather than a fix.

Do digital receipts create duplicate customers?

They can. When a customer chooses Email or Text for their receipt, Shopify POS uses that email or phone number to create a customer profile and attaches it to the order.

The receipt options are Email, Text, Print and No receipt, plus Shop app when the customer's details match a Shop account. The customer picks on a customer-facing display, such as a POS Terminal or the Customer View app, or staff turn the device toward them. Shopify's documentation says that when no existing match is found, the customer sees an Enter email or Enter phone screen.

The duplicate happens when the contact the customer types differs from the one on their online profile. A shopper who buys online with a work email and asks for an in-store receipt by text has given you two unconnected identifiers. Shopify's documentation doesn't say POS matches a phone number to a profile that only has an email, so the safe assumption is that it creates a separate profile.

Why do cashiers create duplicate profiles?

Mostly because adding a new customer is faster than finding the existing one, and POS search won't always find them by the detail the customer offers.

Shopify's POS search pages describe searching by name or email from the Add customer screen, the global Search bar (tap Customers) or the Customer icon in the navigation bar, with match reasons shown in the results. The cart's Add customer steps name only name or email. If a customer gives their phone number and the cashier can't find them, the quickest fix at a queue is Add new customer, and now there are two.

Two other cashier habits cause trouble later even when they don't create duplicates directly:

• Placeholder details. Typing the store's own address or phone on walk-in profiles makes dozens of unrelated customers share a value, which confuses any later matching by address or phone.
• First-name-only profiles. "Sam" with no surname or contact can't be matched with confidence to anything.

How to reduce POS duplicates at the counter

You can't prevent every POS duplicate, but you can make the counter produce profiles that are easy to connect. The biggest lever is Required customer information, which is a POS Pro feature.

To set it up:

1. In the Shopify admin, go to Sales channels > Point of Sale.
2. In Customize the in-store experience, click Edit Point of Sale.
3. Click the settings icon in the POS editor menu bar.
4. Click Required customer information and choose which details to collect: first name, last name and contact information.
5. For contact information, choose phone only, email only, email or phone, or both, and set each detail to Not required, Recommended or Required.
6. Click Save.

Shopify notes that this works only for locations on a Shopify POS Pro subscription, that staff need the Manage required checkout information in the POS channel permission, and that POS should be on the latest version for the checkout validation to work. Staff can still add items without the details, but they're prompted for the missing information before checkout, in an Add missing cart information view where they can search for an existing customer or enter a new one.

Choose Recommended over Required for most stores. With Required, staff can't complete a sale when a customer declines to share details, which costs sales. Recommended prompts every time but lets staff skip.

How to clean up duplicates created by POS

Find the POS customers, compare them with everyone else, and merge the confirmed pairs in the admin. Shopify's POS help pages cover creating, searching and editing profiles in the app but not merging, so the cleanup happens in the Shopify admin.

Start by isolating in-store buyers. Shopify's POS segment examples use orders_placed(app_id:(129785)) = true in the segment editor on the Customers page for customers with POS purchases, and orders_placed((location_id: ######)) = true for a specific location. Filtering by location tells you whether one store or one pop-up is the main source.

Then export and compare. Our guide on how to find duplicate customers in Shopify has the spreadsheet method: normalize emails and phones, group rows that share one, and review each group. For POS data, add one pass for name-only profiles. Sort by last name, and for each profile with no email and no phone, look for a profile with the same name that does have contact details. Treat these as candidates, not matches. Check order dates, the location and the items before you merge, because two different people called Chris Lee is an ordinary Tuesday.

To merge, open one profile and click More actions > Merge customer. Under Find a customer to merge with you can search by first name, last name, email, phone or credit card number, which helps with card-created profiles. Review the merged result and click Merge, then Confirm. Shopify keeps the profile with an email when only one has one, the merge can't be undone, and some profiles refuse to merge, such as those with store credit or a vaulted credit card. Our article on why Shopify won't merge some customers lists every blocker. For the broader picture of where duplicates come from beyond the counter, see why Shopify creates duplicate customer profiles.

Run the cleanup after a busy retail season or event, and monthly if POS is a large share of your sales.

How Twinfold helps

Twinfold is a Shopify app by NewClick (independent, not made by Shopify) that finds duplicate customers and merges them in bulk after a preview. It doesn't change how POS creates profiles; it helps with the cleanup.

Scan for duplicates reads your whole customer list through Shopify's bulk export, free on every plan. Three of its matching rules fit POS data: Email variant (the same address after lowercasing, removing a "+tag", and removing Gmail dots), Same phone (one profile's phone found on another profile's address, with matching names) and Same name and address. Values shared by more than 20 customers, such as a store address typed as a placeholder on POS sales, are ignored so they can't group strangers.

Be clear about one limit: a name-only profile from a chip card has no email, phone or address, so Twinfold has nothing to match it on. Those still need the manual name review above. For the rest, every merge is previewed with Shopify before you confirm, and groups you mark Not duplicates stay out of future scans.