Why doesn't Shopify or Squarespace catch duplicate customers automatically?

Shopify and Squarespace identify customers by email address. If the same person checks out with two different emails — a guest checkout plus a later account, or a work email and a personal email — each platform creates a separate customer record. There is no built-in fuzzy match on name or shipping address.

What columns should I match on to find duplicate ecommerce customers?

Match on First Name, Last Name, and Shipping Address. Leave email out — that's the field where the duplication is hiding. Adding phone number is a good secondary signal if it's populated in your export.

Does this work with WooCommerce or BigCommerce exports?

Yes. Any platform that lets you export your customer list as a CSV will work — WooCommerce, BigCommerce, Wix, Magento, or anything else. The matching is on the file itself, not the source platform.

Duplicate Customers in Your Shopify or Squarespace Export? Fix It in Under 5 Minutes

Q: Why won't Excel's Remove Duplicates work for this?

Excel's Remove Duplicates only catches exact matches. 'Ann Russell' and 'A. Russell' at the same address stay as two separate rows. Same with 'ann.russell@gmail.com' and 'annrussell@hotmail.com'. You need fuzzy matching to catch near-duplicates.

You exported your customer list. Now you're staring at the same person twice — different email addresses, same name, same address.

This happens constantly. Someone checks out as a guest, then creates an account. Someone uses their work email once and their personal email next time. Your platform has no way to catch it.

Here's how to find them.

Why your platform won't catch this

Shopify and Squarespace treat each email address as a separate customer. There's no built-in check for "same person, different email." So your list grows — and your open rates drop, your segment counts inflate, and your suppression lists get messy.

You can't fix what you can't find.

What you're looking for

Duplicate customers who share:

The same name (exact or close — "Ann Russell" and "A. Russell")
The same shipping address
Sometimes the same phone number

Different emails make them invisible to exact-match tools. You need fuzzy matching to surface them.

How to find them in under 5 minutes

Step 1. Export your customer list from Shopify or Squarespace as a CSV.

Shopify: Customers → Export → All customers
Squarespace: Contacts → Export

Step 2. Upload it to Clean by Similarity API.

Step 3. Select First Name, Last Name, and Shipping Address as your matching columns. Leave email out — that's the field causing the problem.

Step 4. Run. Review the clusters — each group shows you records the tool thinks belong to the same person, with a similarity score.

Step 5. Download your deduplicated list or the cluster view to review manually.

That's it. No formulas. No coding. No VLOOKUP.

Ready to dedupe your Shopify or Squarespace export?

Upload your CSV and find duplicates in seconds — no signup, no install, 500 rows free.

Try it for free →

What to do with the results

Once you have your clusters:

Merge in your platform — keep the account with the most order history, remove or merge the other
Clean your email list — suppress the duplicate address before your next send
Update your CRM — if you're importing into HubSpot, Salesforce, or similar, deduplicate first or you'll import the problem

Why not just use Excel?

Excel's Remove Duplicates works on exact matches only. "Ann Russell" and "A. Russell" at the same address stay as two separate rows. Same with "ann.russell@gmail.com" and "annrussell@hotmail.com."

Fuzzy matching catches the near-matches Excel misses. That's the difference.

Works with any CSV export — Shopify, Squarespace, WooCommerce, BigCommerce, or anything else you can download as a file.