Order Merge checks both orders before it changes anything. If a pair is refused, you see This pair can't be merged yet with the reasons listed, and neither order is touched. Here is what each reason means.
Refusal reasons
You see | What it means | What to do |
These orders belong to different customers | Only one customer's orders can be combined. | Pick two orders from the same customer. |
These orders were placed in different currencies | The two orders were paid in different currencies. | These cannot be combined. |
Hasn't been paid in full yet | One order still has money to collect. | Wait until it is paid. |
Settle the refund on #1146 first, then merge. | The order has a refund still to settle: a refund Tacey recorded and nobody has paid out yet, a refund waiting for your approval, or a refund that failed. | Open the order (the page links it), settle the refund, then merge. |
Settle the payment owed on #1146 first, then merge. | The order has a payment still to collect, or a payment Tacey is still waiting on. | Collect or settle it on the order, then merge. |
A recent edit on #1146 hasn't been confirmed yet | A change to the order was made but Shopify has not confirmed it yet. | Give it a few minutes, or open the order to check, then merge. |
Store credit was issued outside #1146 | Store credit was given to the customer outside the order, so the order's balance in Shopify can't be relied on. Tacey also refuses to add items to or refund such an order. | Review the order first, then merge. |
Shopify shows a refund still owed on #1146 / a payment still due on #1146 | Shopify's own balance for the order is not zero, even if the order reads Paid. | Refund or collect the balance in Shopify, then merge. |
Couldn't read the balance / check the refunds and payments on #1146 | Tacey could not confirm the order's money is settled, so it won't guess. | Try again in a moment. |
Its shipment was already combined with another order | The order is part of a Combine duplicate orders pair, where Tacey merged two orders' shipments. Cancelling it here could cancel half of that parcel. | These cannot be merged. Ship the combined parcel as it is. |
Has at least one fulfilled item | Something on it has already shipped. | These cannot be combined. |
Has an active return in progress | A return is open on it. | Finish the return first. |
Already cancelled | One order is cancelled. | Pick an open order. |
Already part of a merge / Already combined into another order | One order was merged before. | An order can only be merged once. |
Placed more than 60 days ago | The order is too old. | Only recent orders can be combined. |
Blocked by a store tag | The order carries one of your Blocked order tags. | Remove the tag in Shopify if you want to merge it. |
Has a subscription item | Merging subscription orders isn't supported yet. | Fulfill them separately. |
Placed through a business account | A B2B order. | Not supported. |
Placed in a physical store | A point of sale order. | Not supported. |
Created as an invoice rather than through checkout | A draft order. | Not supported. |
A local pickup order | Nothing ships, so there is nothing to combine. | Not supported. |
You picked the same order twice | Both boxes hold the same order. | Pick a different second order. |
Each reason tells you which order it applies to, so if only one of the two is a problem you can swap it for another.
Why money still to settle blocks a merge
A merge adds the second order's items to the first and cancels the second. If either order has a refund, payment or store credit still to settle, the cancel could leave the customer's money stranded, so Order Merge refuses until it is settled. It checks all of these, on both orders, every time you open a pair and again at the moment you confirm:
An unsettled record on Tacey's Order changes page: a refund owed (including one waiting for your approval), a payment owed or pending, a failed refund, a failed capture, or an edit Shopify hasn't confirmed.
Store credit issued outside the order.
A balance in Shopify that is not zero, in either direction, whatever the order's status says.
Settled records (a refund that went out, a payment that came in) never block a merge. If a merge was interrupted and you retry the same pair to finish it, that merge's own records don't block it either.
The same check decides what the Merge with another order action on Shopify's order page offers, and what Suggested merges lists.
When the page says "Can't merge right now"
"This order is currently being edited by a customer and can't be merged right now. Try again in a few minutes." The customer is changing the order on their order page. Wait a few minutes and try again.
When a merge did not go through
In Merge History (open Order Merge, then View on the Merge History card), each attempt has a status.
Did not go through. "Nothing changed. #1023 and #1024 are exactly as they were before." No items moved, no order was cancelled, no payment was affected.
Partially combined. This is the one to act on. The second order's items were added to the first, but cancelling the second order failed, so it is still open. Right now both orders show those items. The history explains: "Check #1024 in Shopify before fulfilling either one, so nothing ships twice."
To fix it, cancel the second order in Shopify yourself, without refunding it, since its items now ship under the first order. Until it is cancelled, trying to merge that second order with anything else is refused with: "Already added to another order, but that merge wasn't finished. The other order was never cancelled. Cancel it in Shopify, or retry that same merge to finish it, before trying this one."
Try this merge again only appears on attempts that Did not go through, because nothing was changed on either order. It takes you back to the merge page with both orders filled in, where every check runs again.
The history also shows Shopify's own reason where there is one, for example "This order can't be cancelled because it already has a fulfillment on it."
Combined. Everything worked.
What you can do instead
If a pair cannot be merged, you can still ship the orders together by hand in Shopify. Tacey will not record that as a merge.