Everything about how Order Merge behaves on your store lives on one page, Merge settings. Open Order Merge in the Tacey menu, then choose Open settings on the Merge settings card. Change what you need and use Shopify's Save bar at the top of the page. A Merge settings saved message confirms it. If the save fails you see Could not save merge settings. Try again. and nothing is changed.
None of these settings moves money. Merging two orders yourself is covered in How do I combine two Shopify orders into one shipment?, and what happens to a duplicate shipping charge is in Does merging orders refund the extra shipping or email the customer?.
Combined order
The combined order is the order that keeps all the items after a merge.
Setting | What it does | Default |
Tag the combined order | Adds a tag to the combined order so you can filter your merged orders in Shopify. | On |
Tag name | Shown when the tag switch is on. Pick one of the tags your orders already use, or choose Choose or create a tag to type a new one. Only one tag is allowed. | tacey-merged |
Add a note naming the absorbed order | Leaves a staff note on the combined order saying which order was combined into it. Only your team sees it. | On |
Tag rules to know:
Spaces become hyphens, commas are removed, and a tag is cut at 40 characters.
If you switch the tag on and leave it empty you see No tag chosen. Pick one of your order tags or type a new one.
You cannot use a tag Tacey adds for its own bookkeeping: tacey-validated, tacey-corrected, tacey-check-address, tacey-edited, tacey-gift-message, tacey-refund-owed, tacey-payment-owed, or anything starting with tacey-merged-into-. You see a message saying the tag is one Tacey uses and asking you to pick another name. Nothing is saved until you do.
Absorbed order
The absorbed order is the order that is cancelled after its items move onto the combined order.
Setting | What it does | Default |
Cancellation note | Not a setting, always on. Every absorbed order is cancelled with the note "Merged into #1042 by Tacey" (with the real order number). Shopify has no "merged" cancel reason, so the reason reads Other and the note says where the items went. | Always on |
Tag the absorbed order | Adds a tag with the number of the order it went into, for example tacey-merged-into-1042. | On |
Duplicate shipping
This section has no controls. It explains that Tacey adds the second order's items to the first and cancels the second, and that nobody is charged again. If both orders paid for shipping, Merge History marks the second charge Refund owed and you refund the exact amount with one click. Choose Open merges with a refund owed to see those merges.
Suggestions (Smart Suggest)
Smart Suggest lists pairs worth merging on the Order Merge home page. Nothing is merged until you review a pair and confirm it.
Setting | What it does | Default |
Suggest merges | Turns the Suggested merges list on the Order Merge home on or off. When it is off, the page tells you the list is hidden. | On |
Placed within | Two orders are a pair only when they were placed this close together. Choices: 12 hours, 24 hours, 48 hours, 72 hours, 7 days. | 48 hours |
Require the same shipping address | When on, pairs that ship to different addresses are left out. When off, those pairs are listed and marked, and you choose which address ships. | Off |
Repeat orders: what happens on its own
This section answers one question, When a customer places another order to the same address, with three choices. It never affects merges you start yourself.
Choice | What happens |
Do nothing (default) | Both orders stay as they are. You can still merge them yourself or from Suggested merges. |
Ship them together (keep both orders) | This is the Combine duplicate orders tool. The page warns you that this cannot take effect on Shopify today: Shopify only combines the shipments of one order, never of two separate orders. A pair found while this is chosen is recorded as not combined, and nothing changes on either order. To send one parcel, choose Merge them into one order. |
Merge them into one order | This is automatic merging. The second order's items move onto the first and the second order is cancelled. Ship them together is switched off while this is chosen. |
Turning automatic merging on
Choosing Merge them into one order shows a warning, Before you turn this on. It says the newer order is cancelled for good and its items move onto the older one, with no undo, that your customer is emailed that the orders were combined, and that no money moves. Tick I understand, turn automatic merging on and save. If you do not tick the box, Tacey says Tick the box to confirm before turning automatic merging on. Nothing was saved. You are asked once; if it is already on you are not asked again.
Automatic merging
The Automatic merging section shows an On or Off badge. It is only on when the repeat-order choice above is Merge them into one order. While it is off the section says It is off. To turn it on, choose "Merge them into one order" under When a customer orders again, then save. Choosing Do nothing or Ship them together always means automatic merging is off.
What automatic merging does
It checks for pairs every 15 minutes. It merges a pair only when all of this is true:
the two orders are from the same customer and ship to the same address
both are paid in full and neither has shipped
no refund or store credit is owed on either
neither order has a Shopify fraud risk above low, and Shopify has finished assessing both (an order under an hour old that Shopify has not rated yet waits)
neither has a fulfillment hold that Tacey did not place
both orders are at least 15 minutes old (a customer may still be editing)
the orders were placed within your window, and neither carries a tag you excluded
The older order keeps every item, the newer order is cancelled, and no money moves. If shipping was paid twice, the amount waits in Merge History for you to refund. Your customer is emailed that the orders were combined, and you get your merge email if that switch is on.
Automatic merging settings
Setting | What it does | Default |
Which pairs may merge on their own | Every pair that is safe to merge: any two orders from the same customer to the same address that pass every safety check. Only orders that match my rules: a pair merges only when both orders match one of your active automatic rules. | Every pair that is safe to merge |
Orders placed within | Two orders are merged only when they were placed this close together. Choices: 1, 3, 7, 14, 30 or 59 days. | 7 days |
Never merge orders tagged | An order with any of these tags is left alone, whatever your rules say. Tags are not case-sensitive. Up to 20 tags. Shown as No tags. Every safe pair can merge. when empty. | No tags |
Merge rules card | Opens the Rules page and shows how many rules are on, draft or off (or No rules yet). Write the rules there, see How do rules work? | n/a |
Show the pairs it would merge right now | A preview of the next pass. It reads your live orders, merges nothing and lists each pair as "#1001 keeps the items, #1002 is cancelled". It also says how many pairs were found and left alone because they were not safe, and when the list is cut short. | n/a |
When it is on but cannot fire
Tacey says so next to the controls instead of leaving you to wonder:
Only orders that match my rules with no active rule that includes automatic merging shows Automatic merging is on, but no active rule includes any order, so nothing will be merged. Add a rule, or switch to every pair that is safe to merge.
The repeat-order choice is Ship them together: the warning above applies and nothing is merged.
Turning it off takes effect within 15 minutes. A merge that is already running finishes.
What you see after it has run
Last checked [time]. Merged [number] on that pass. is the result of the last pass.
This pass checked X of Y groups of orders. The newest are checked first; the rest are checked on the next pass. appears on a very busy store.
The last pass stopped early: [reason] It will try again in 15 minutes. appears if a pass could not finish.
Pairs that could not be merged after three tries, which need your attention: [number] with an Open Merge history link. A merge that moves the items but cannot cancel the second order is retried after 15, 30 and then 60 minutes, and moved to needs attention after three failed tries.
Every automatic merge is recorded in Merge History like a manual one.
Notifications
Setting | What it does | Default |
Email me when a merge completes | One email for each completed merge. Nothing is sent for a failed or partial merge. | On |
The email goes to your store notification email, shown on the page. Choose Change it in Global Settings to change it. If no address is set, the page says This is on, but nothing will send and asks you to add one under Email in Global Settings. When the switch is off the page says no email is sent when a merge completes. If some email authentication checks for your sending domain are failing, the page warns that merge emails may not deliver reliably. Who the email comes from is explained in Who do Tacey's emails come from, and what do they contain?.
What this does NOT do
It does not undo a merge. The absorbed order is cancelled for good. Decide with the safety checks in mind, and use Show the pairs it would merge right now before you switch automatic merging on.
It does not merge pairs that are not safe. Orders from different customers, to different addresses, partly shipped, with a refund or store credit owed, with a fraud risk above low or with a fulfillment hold from another app or person are never merged automatically.
It does not refund shipping on its own. The extra shipping charge waits in Merge History until you refund it.
It does not combine shipments. Ship them together cannot take effect on Shopify today.
It does not change merges you start yourself. The repeat-order choice only decides what happens on its own.
It does not look back more than 59 days.
Frequently asked
I turned automatic merging on and nothing merged. Why? Check the page. The usual reasons are the scope being Only orders that match my rules with no active rule, a window that is too short for when the two orders were placed, a pair that fails a safety check, or an order that is under 15 minutes old. Show the pairs it would merge right now tells you what the next pass would do, and Pairs found and left alone because they are not safe to merge tells you how many it skipped.
Can I stop one customer's orders being merged? Add a tag you use on that order to Never merge orders tagged.
Why did Tacey refuse the tag I chose? It is one of the tags Tacey writes for its own bookkeeping. Pick another name.
Which orders can be merged at all? See Why can't these two orders be merged?.
Not yet driven
The preview on the dev store answered "We could not check right now. Try again in a moment." on 2026-10-10, so the list of pairs it shows was not seen on a real run. The 15 minute pass, the retry timings and the needs attention counter are described from the code and its unit tests, not from a watched run on a store.