Short answer
Shopify creates a separate customer profile for almost every variation of
the same person — guest checkout versus account, a different email, a typo, POS versus online. There is
no native merge tool. You can delete a profile, but you cannot combine two, and deleting loses
the order history attached to it.
That matters more than it looks, because duplicates cost you
twice: once in corrupted analytics and split loyalty points, and again on every app you pay for per
customer. Deduplicating is one of the few cleanup jobs that can pay for itself in the same month.
Why Shopify makes duplicates
None of these are bugs. They are the ordinary consequence of how the platform identifies a customer, and they
happen to every store at some volume.
Guest checkout, then an account
The same person buys as a guest in March and creates an account in June. Two profiles, one shopper, and the
first order is invisible from the second profile.
A second email address
Work address one time, personal the next. Shopify keys on email, so these are two entirely unrelated
customers as far as your reports are concerned.
Typos and case
A missing letter or an extra dot in a Gmail address creates a permanent second profile that will never
reconcile on its own.
POS and online
The same regular buys in store and online. Unless the email is captured identically both times, you get two
histories for one relationship.
Phone-only orders
Orders captured by phone or created manually often carry no email or a placeholder, which never links to the
customer’s real profile.
Imports and migrations
Moving from another platform, or importing a marketplace order file, is the single most reliable way to double
your customer list overnight.
What duplicates actually cost
Most guidance stops at “it makes your data messy”, which is true and unpersuasive. Here is the
specific damage:
| Where it hurts | What actually happens |
|---|---|
| Loyalty points | Points split across two profiles. The customer sees a balance that does not match their spending, contacts support, and someone reconciles it by hand. |
| Lifetime value | Every LTV, repeat-rate and RFM number is understated, because one customer with four orders reads as two customers with two. Your best segments look smaller than they are. |
| Email marketing | The same person gets the same campaign twice, and your “lapsed customer” flow fires at someone who bought last week under their other email. |
| Support | An agent opens the profile and sees one order instead of six. The customer has to explain their own history. |
| Returns and fraud checks | Repeat return patterns are invisible when they are spread across profiles. |
| Your app bills | Every app that prices per customer is charging you for the copies. See below. |
The part nobody mentions: duplicates are billable
Loyalty apps, email platforms, review apps and customer-data tools
routinely price on customer or profile count. If 15% of your list is duplicated, you are paying
15% more on every one of those subscriptions, every month, in perpetuity. On a store with 40,000 customers and
three per-customer tools, that is often more than the cleanup costs. It is also the one cleanup task with a
finish line — you do it once, then maintain.
What Shopify gives you natively
Very little, and it is important to know that before you go looking for a setting that does not exist.
- There is no merge function. You cannot combine two customer profiles in the Shopify
admin. - Deleting is not merging. Deleting the duplicate removes its order history with it, which is
usually worse than the duplicate. - You can edit an email on a profile, which sometimes lets you consolidate future orders
— but it does not move past orders across. - Exporting to CSV lets you find duplicates, but there is no import path that merges them back
together.
So the honest free option is: export your customer list, sort by name and by normalised email, and work out
how bad the problem is. That costs nothing and tells you whether it is worth fixing at all. If duplicates are
under a percent or two of your list, close the spreadsheet and spend the time elsewhere.
Find out how bad it is, free
- Export customers from Shopify admin as CSV.
- Normalise the emails — lowercase everything, and for Gmail addresses strip dots and
anything after a+, since those all deliver to one inbox. - Count duplicates on that normalised column, then again on name plus postcode to catch the
people using two different addresses. - Divide by your total customers. That percentage is your answer. Under 2% is noise. Above
10% is distorting every report you look at and inflating every per-customer bill you pay.
The part that makes it a maintenance tool rather than a one-off clean-up: real-time detection when a new customer is created, a weekly scheduled scan, and an email digest. Duplicates accumulate quietly, so catching them as they appear beats another big cleanup in a year.
When it is worth an app
Singulary — Merge Customers is built specifically for this: it scans for
duplicate profiles, shows you what it found, and merges them while keeping the order history intact — the
part the manual route cannot do.
| Plan | Price | What you get |
|---|---|---|
| Test | Free | 1 scan, up to 10 merges, limited view of duplicates. Enough to size the problem, not to fix it. |
| Growth | $9/mo | Unlimited scans and merges, full duplicate list, bulk merges, auto-detection of new duplicates, data health fixes. Up to 25,000 customers. |
| Business | $49/mo | Same features, up to 100,000 customers. |
| Enterprise | $99/mo | Same features, unlimited customers. |
Note the meter: customer count, not merges. The features are identical across all three paid
tiers — you are paying purely for list size. That is unusually honest pricing, and it means a small store
with a filthy list pays $9 while a large store with a clean one pays $49.
Pros ✓
- Merges while preserving order history — the thing Shopify cannot do at all
- Carries the Built for Shopify badge, which is uncommon for an app this small
- Auto-detects new duplicates, so it is a maintenance tool rather than a one-off
- Free tier is enough to scan and confirm whether you have a problem worth paying to fix
- Identical features on every paid tier — no feature gating, just list size
Cons ✕
- Only 9 reviews — a 5.0 average on that base is encouraging, not proven
- Merging is destructive and hard to undo; test on a handful before any bulk run
- Priced on total customers, so a large clean list still pays the higher tier
- The free tier’s 10 merges are a demonstration, not a solution
- We have not run it on a live store — this is from the listing and its pricing
Before any bulk merge: export a full customer backup. Merging is not reversible in any
meaningful way, and an automated match on name alone will happily combine two different people who share one.
Run a scan, merge five by hand, check those five orders and loyalty balances survived, and only then let it work
in bulk.
See Singulary → Partner link · free tier · $9/mo to 25k customers
Keeping it clean afterwards
- Ask for email at POS. The single biggest source of ongoing duplicates in a store that sells
both in person and online. - Encourage accounts without forcing them — a logged-in repeat customer never duplicates
themselves. - Normalise on import. Lowercase every email before a bulk import, every time.
- Re-scan quarterly rather than annually. Duplicates accumulate quietly, and a small regular
clean is far easier than another big one.
Bottom line
Do the free CSV check first. It takes twenty minutes and it is the only way
to know whether this is a real problem on your store or a tidy-up you do not need.
If duplicates are above roughly 5% of your list, an app is
worth it — not mainly for the tidiness, but because your loyalty balances, your repeat-rate reporting and
every per-customer subscription you pay are all wrong by that percentage. At $9 a month to 25,000 customers,
Singulary is cheap against that. Just note the 9-review base and merge carefully. See Singulary → Partner link · free tier · $9/mo to 25k customers
FAQs
Can you merge duplicate customers in Shopify?
Not natively. Shopify has no merge function for customer profiles. You can edit an email or delete a profile,
but deleting takes that profile’s order history with it. Combining two profiles while keeping both order
histories requires an app.
Why does Shopify create duplicate customers?
Because it identifies customers primarily by email. Guest checkout followed by account creation, a second
email address, a typo, POS versus online orders, phone orders without an email, and platform migrations all
produce a second profile for the same person.
Do duplicate customers cost money?
Yes, in two ways. They distort lifetime value, repeat rate and loyalty balances, and they inflate every
subscription that prices per customer or per profile — loyalty apps, email platforms, review tools. If 15%
of your list is duplicated you are paying roughly 15% too much on all of them, every month.
How do I find duplicate customers for free?
Export your customers to CSV, lowercase the email column, strip dots and any +suffix from Gmail
addresses, then count duplicates on that normalised column and again on name plus postcode. The resulting
percentage tells you whether it is worth fixing.
Is merging customers reversible?
Not in any practical sense. Export a full customer backup first, merge a handful manually, verify the order
history and loyalty balances survived, and only then run anything in bulk. Automated matching on name alone can
combine two genuinely different people.
How much does Singulary cost?
There is a free tier covering one scan and ten merges. Paid plans are $9 a month up to 25,000 customers, $49
up to 100,000 and $99 for unlimited. The features are identical on all three — you are paying for list
size, not capability.
App rating and pricing verified against the Shopify App Store on 25 August 2026, where
Singulary showed 5.0 from 9 reviews with the Built for Shopify badge. We have not installed and run this app;
this page reports what the listing discloses and recommends the free CSV check first. Contains a partner link,
which never costs you more. Shopify’s native capabilities change — confirm before relying on any
described limitation.