US merchants fulfill TikTok 4PL orders by clicking Fulfill on TikTok, selecting the items to ship, entering the package weight in pounds and dimensions in inches, choosing a TikTok-supported US carrier such as USPS Ground Advantage, then clicking Create Package. SPL sends the shipment to TikTok, generates the shipping label, and syncs tracking automatically. You can do this from the SPL Orders dashboard or directly inside your Shopify Admin using the SPL fulfillment block.
The US 4PL flow gives you a little more to fill in than other regions, weight, dimensions and the actual shipping service, but in exchange you see the carrier and its price up front, and TikTok still handles label generation and tracking sync for you.
This guide walks the US workflow step by step, including the measurements that keep carriers from rejecting a package.
US or general 4PL, which flow is this?
This guide covers the US 4PL workflow, where you enter package weight and dimensions and pick a US carrier like USPS, with the price shown.
If you are outside the US, the general flow is a little simpler: TikTok selects the carrier and you just choose a handover method. See our general 4PL fulfillment guide for that version.
TikTok Shop Integration — SPL
Lets US merchants ship TikTok 4PL orders with TikTok-supported carriers like USPS, generating labels and syncing tracking between TikTok and Shopify automatically. Fulfill from the dashboard or right inside Shopify Admin.
What US 4PL fulfillment is
The 4PL, or Fourth-Party Logistics, Fulfillment feature lets US merchants ship TikTok Shop orders using TikTok-supported logistics carriers such as USPS. It automatically syncs tracking details between TikTok and Shopify and reduces manual shipping work. The difference from other regions is that the US flow has you provide package measurements and choose the shipping service yourself, so you can identify, prepare and ship each order precisely.
Where to find 4PL orders
- Open Shopify Admin.
- Go to Apps, then TikTok Shop – SPL.
- Click Orders from the left sidebar.
You will see order tabs such as All, Unfulfilled, Awaiting Collection, In Transit, Delivered and Cancelled. When an order is eligible for fulfillment, the Fulfill on TikTok button becomes active.
Step 1: Click Fulfill on TikTok
- Locate the order in the Orders list.
- Click Fulfill on TikTok in the Tracking Info column.
- A popup titled TikTok Shipping Fulfillment (4PL) opens.
Step 2: Select the items to fulfill
Inside the popup, under Create New Package, you will see a list of products.
- Tick the checkboxes for the items you want to ship.
- Multiple quantities of the same SKU may appear, so make sure your selection is correct.
Step 3: Enter package details
Under Package Details, provide the shipping measurements. This is the part unique to the US flow, and getting it right matters.
Weight
Enter the total package weight, and select the correct unit, usually POUND in the US.
Dimensions
Enter L (length), W (width) and H (height). The unit is typically INCH.
Step 4: Select the shipping service
In the Shipping Service dropdown, choose a TikTok-supported US carrier. For example, USPS Ground Advantage – USPS (USD $3.43).
The available services depend on your TikTok Seller Center carrier configuration and warehouse location, so if a service you expect is missing, that is usually where to check. For managing which carriers appear, see our guide to setting up shipping carriers.
Shipping US TikTok orders? SPL generates USPS and other TikTok-supported labels and syncs tracking automatically, from the dashboard or inside Shopify Admin. Free to install, plans from $9.99/month.
Install SPL free →Step 5: Create the package
Click Create Package. The SPL app will:
- Send shipment data to TikTok.
- Generate a shipping label.
- Sync tracking automatically.
Once tracking syncs, you can monitor progress from the Orders dashboard as the status moves through the fulfillment stages. If you are unsure what each stage means, our guide to understanding order status in SPL covers them.
Alternative: fulfill directly from Shopify Admin
You can also fulfill 4PL TikTok orders directly inside your Shopify Admin, without opening the SPL app dashboard. This suits merchants who manage every order from Shopify and prefer not to switch between apps.
- Go to Shopify Admin, then Orders.
- Open the TikTok order you want to process.
- Scroll down to the Blocks section.
- Click the SPL TikTok Order Fulfillment block.
- Click Create TikTok Shipping Label.
- Select the package and confirm fulfillment.
Once confirmed, the system sends fulfillment details to TikTok, generates the shipping label, and automatically syncs tracking, exactly as the dashboard method does.
Important notes for US merchants
✓ Use accurate weight and dimensions to avoid carrier issues
✓ If the Fulfill on TikTok button is disabled, check the conditions below
When Fulfill on TikTok is greyed out, it is usually one of these:
| Check | What it should be |
|---|---|
| Payment | The order is paid, not unpaid. |
| Package status | Status is TO_FULFILL. |
| Carrier service | A carrier service is configured. |
If an order is not appearing or syncing at all, that is a different issue, covered in TikTok Shop order sync issues.
When to use 4PL fulfillment
Use 4PL if you want:
✓ Automatic tracking sync
✓ Reduced manual shipping effort
✓ Integration with TikTok-approved US carriers
US 4PL fulfillment FAQs
Why is the Fulfill on TikTok button disabled?
It is usually one of three things. Check that the order is paid, that the package status is TO_FULFILL, and that a carrier service is configured. If any of those is missing, the button stays greyed out. Confirming your warehouse address is set correctly in TikTok Seller Center also helps, since the available shipping services depend on your carrier configuration and warehouse location.
What weight and dimension units does the US flow use?
Weight is usually entered in POUND, and dimensions, meaning length, width and height, in INCH. Select the correct unit as you enter each value. Accurate measurements are important, because incorrect weight or dimensions can cause shipping price errors or lead to the carrier rejecting the package.
Which carriers can US merchants use?
You choose a TikTok-supported US carrier from the Shipping Service dropdown, for example USPS Ground Advantage. The services available to you depend on your TikTok Seller Center carrier configuration and warehouse location, so the exact list can vary from one seller to another. If a service you expect is not showing, review your carrier setup in Seller Center.
Do I have to upload tracking numbers?
No. When you click Create Package, SPL sends the shipment to TikTok, generates the label, and syncs tracking automatically between TikTok and Shopify. There is no manual tracking upload for 4PL orders, which is one of the main reasons US merchants use it.
Can I fulfill US 4PL orders without opening the SPL app?
Yes. You can fulfill from Shopify Admin. Open the TikTok order, scroll to the Blocks section, click the SPL TikTok Order Fulfillment block, then Create TikTok Shipping Label, and select the package to confirm. It sends fulfillment to TikTok, generates the label, and syncs tracking exactly like the dashboard method, which suits merchants who work entirely inside Shopify.
How is the US flow different from the general 4PL flow?
The US flow has you enter package weight and dimensions and select the actual shipping service, with its price shown, before creating the package. The general, non-US flow is a little simpler: TikTok selects the carrier for you and you mainly choose a handover method such as drop off or pickup. Both generate the label and sync tracking automatically. Our general 4PL guide covers the non-US version.
Keep going
More TikTok Shop guides.
Everything around orders, fulfillment and shipping.