What actually moves between the two systems
When a customer checks out, the storefront holds a record: who ordered, what they bought, where it is going and which shipping option they selected. A label tool needs most of that to create a shipment. A store integration is the connection that copies the record across, and later sends information back.
Data usually flows in two directions:
- Store to shipping tool: order number, recipient name and address, contact details, line items, quantities, item weights, declared values and the shipping method the customer chose.
- Shipping tool to store: the carrier, tracking number and a “shipped” status, which lets the store email the customer and mark the order as fulfilled.
If either direction fails, you get either orders that never reach the label screen or customers who never receive tracking details.
How the connection is made
There are a few common patterns, and a given product may support more than one.
Built-in connectors. The shipping tool offers a ready-made link to a particular storefront or marketplace. You typically sign in to the store, approve access and choose which orders to import. This is the simplest route, and the one most small sellers use.
Plugins or apps inside the store. Some storefronts let you install an extension that sends orders to the shipping tool, or that shows carrier options at checkout.
APIs. An API lets two systems exchange data programmatically. Developers can use it to build a custom connection when no ready-made one exists. It offers flexibility but needs maintenance whenever either side changes.
File import. A spreadsheet or CSV exported from the store and uploaded to the tool. It is manual, but it works as a stopgap and is useful for one-off bulk jobs or marketplaces without a connector.
Connections work either by polling (the shipping tool asks the store for new orders every few minutes) or by notifications (the store pushes each new order as it is placed). Polling means a short delay is normal; notification-based links are usually quicker but still not guaranteed to be instant.
Field mapping: where problems tend to start
The two systems rarely describe an order in identical terms. The store might have a shipping method called “Standard (3-5 days)”, while your label tool knows services by carrier names. Mapping means telling the tool which service to use for each store option. If a mapping is missing, the order may import with no service selected, or with a default that does not match what the customer paid for.
Other mismatches are common:
- Weights and units. A product in grams in the store and ounces in the tool can produce wrong weights unless the units are set deliberately.
- Address fields. Some stores give one street line, others two or three; long lines may be cut when printed. Poorly formatted text is a frequent cause of address errors.
- Phone numbers and emails. Some carriers require a phone number for certain services, particularly international ones. If the store does not make it mandatory at checkout, the label tool may reject the order.
- Customs data. International orders need product descriptions, values and often tariff codes. These may need to be stored on each product in the shop for them to flow through. See the notes on harmonized codes for what those are.
- Bundled or variant products. A bundle of three items may appear as one line in the store but need separate weights for rating.
Order status and edits
A shipping tool is only accurate as of the last sync. If a customer changes an address or cancels after the order has been imported, the change may not carry across. Many sellers handle this by holding orders for a short period before importing, or by checking the order in the store just before printing. Decide in advance who is responsible for catching late edits, because it is easy to assume the software does it.
Partial shipments need thought too. If one order ships in two parcels, the integration should be able to record two tracking numbers against one order. Not all do.
Handling multiple channels
Businesses selling through a website and one or more marketplaces often connect them all to a single tool so that all orders appear in one queue. This helps with order batching, since labels can be printed together regardless of source. The catch is that each channel has its own rules about how and when tracking must be uploaded, and about deadlines for marking an order as shipped. Check what each channel expects before setting up automatic updates.
Checking that an integration works
Test before depending on it.
- Place a few test orders with realistic details: a long address, a two-line address, an international destination and a multi-item order.
- Confirm that each arrives in the tool with the right address, weight and service.
- Create labels and verify that tracking numbers return to the store and that the customer notification fires.
- Cancel or edit an order and see what happens.
- Check what the tool does when the connection drops. Does it retry, alert you or silently stop?
Afterwards, a regular spot check is worthwhile: compare the number of paid orders in the store against the number in the shipping tool at the end of the day.
Security and access
Connecting systems means granting one access to the other. Approve only the permissions needed, use individual logins rather than a shared one, and remove access for tools you no longer use. Treat the access credentials as you would a password. This is a small, practical part of managing cybersecurity risks in your shipping setup.