Ecommerce order fulfillment process from checkout to delivery

Every order spends part of its handling time waiting. It sits in the sales channel until it reaches your order system, then on the pick list until someone picks it, then as a labeled package until the carrier collects it. Those waits count against your ship-by date the same way picking and packing do.

For marketplace sellers, each marketplace also decides what counts as a late shipment. Amazon checks whether you confirmed shipment by the ship-by date. eBay checks whether the carrier scanned the package within your handling time.

To find out where you can improve your order fulfillment process, measure how long your late orders spent in each waiting stage.

What is ecommerce order fulfillment?

Ecommerce order fulfillment covers every step from receiving inventory to the buyer’s package arriving, plus any returns. Ecommerce product fulfillment is another name for the same process.

The process has six steps:

1. Receive and store inventory
2. Capture the order and allocate inventory
3. Route the order
4. Pick, pack, and verify
5. Hand over to the carrier and confirm shipment
6. Deliver, track, and handle returns

Order management is the record of each order: which sales channel (a marketplace such as Amazon or a webstore such as Shopify) it came from, what was bought, and its status. Your order system holds that record. 

It might be an order management system (OMS) that pulls in orders from every channel, or your webstore’s admin if you sell on one channel. Fulfillment works from that record to know which items to pick and where to send them. Shipping is one step inside fulfillment, from printing the label to the package reaching the buyer’s door.

You can run fulfillment from your own warehouse, hand it to a third-party logistics provider (a 3PL, an outside company that stores your inventory and ships orders for a fee), or send inventory into a marketplace program such as Fulfillment by Amazon. You can also combine fulfillment methods. For example, you could ship webstore orders from your own warehouse while Amazon orders go through FBA. If you’re weighing outsourcing, our guide to how to choose a 3PL provider covers what to look for, and this rundown of ecommerce fulfillment services compares providers.

The order fulfillment process is the same, whoever picks and packs. What changes is where your inventory records live. With a 3PL or FBA, some of your inventory is counted in another company’s system, and those counts have to come back to your order system before your sales channels can rely on them.

Fulfillment is one stage of the wider order-to-cash process, which also covers invoicing and payment. Our guide to ecommerce order management explains how the order record is kept across channels. For ideas on improving each stage, see our nine order fulfillment strategies.

Step 1: Receive and store inventory

Every order depends on work done before the buyer clicks. When inventory arrives from a supplier, someone counts it against the purchase order, checks it for damage, and puts it away in a known location. That location is recorded in your inventory management software. Until the system receives the inventory, no sales channel can sell it, and a count that is wrong at the dock stays wrong at every later step, showing up as oversells, mis-picks, and cancellations.

If you use a 3PL or FBA, receiving happens in their warehouse. You still own the handoff: send an advance shipping notice (ASN, the list of what is arriving and when), and confirm that their received counts come back to your order system before your sales channels sell the inventory.

Step 2: Capture the order and allocate inventory

Handling time starts when the buyer places the order, so any time the order spends in the sales channel before it reaches your order system comes out of that allowance.

If you sell on more than one channel, your order system has to match each channel’s listing (on Amazon, the ASIN) to your internal SKU (stock keeping unit, the code you track each product by). If the listing is mapped to the wrong SKU, the order reserves the wrong product, and whoever picks it pulls the wrong item.

Once the order arrives, it reserves inventory, and every other channel that lists that SKU needs to see the lower count. Until it gets it, a second channel can sell a unit the first one already sold. Linnworks pulls orders from more than 100 sales channels into one order list, and a sale on any of them lowers the shared inventory count that the other connected channels read from, with updates reaching them in under 10 minutes.

“Not having a direct link between our live stock and a sales channel doesn’t work for us,” said Caitlin Barrett, managing director of Marco Paul. The Scottish home and garden seller is present on 20 marketplaces through Linnworks.

Barrett said Marco Paul probably wouldn’t have joined Temu without a direct integration for stock and orders. Temu is now one of the business’s top five revenue streams.

In Linnworks’ 2026 State of Commerce Operations survey of 500 mid-market retailers (annual revenue between $7.5 million and $100 million, split evenly between the US and UK), the average retailer sold on just over four marketplaces, and roughly two-thirds said their inventory visibility across channels and warehouses had at least minor gaps. In fulfillment, that gap means a sales channel shows inventory you don’t have on the shelf. An order placed against it either gets canceled or waits until someone finds the unit or a restock arrives.

Marketplaces track the cancellations an oversell forces. Amazon’s account health target for pre-fulfillment cancellations (orders the seller cancels before shipping), for example, is under 2.5% over seven days. If out-of-stock cancellations cluster on one sales channel, check how often your order system sends updated inventory counts to that channel.

Step 3: Route the order

Routing decides which warehouse ships each order and which carrier service carries it. With one warehouse and one carrier, there’s nothing to decide. Once you add a second warehouse, a 3PL, or inventory in a marketplace program such as FBA, someone has to make that choice for every order, and routing rules can make it for you.

Routing rules check fields already on the order: the sales channel it came from, the destination and package weight, and the shipping service the buyer paid for. A rule can send orders from one channel to a specific warehouse, for example, or send international shipments to one carrier.

The Linnworks Rules Engine can apply rules like these to each order as it downloads, assigning the warehouse and carrier service from conditions you set. Our guide to automated order fulfillment covers which steps to automate first.

Where a carrier returns live quotes (rates calculated for that package when the order comes in), a rule can pick the cheapest service that still arrives within the delivery time the buyer paid for. Not every carrier integration supports live quotes, though. For those carriers, you’ll maintain static rules by hand and update them when the carrier changes its rates. Until you do, a static rule keeps sending orders to the service it was set up for, even after a surcharge makes another service cheaper.

When an order’s items sit in two warehouses, you can split it into two shipments or hold it while the missing item is transferred to the warehouse holding the rest. Splitting costs a second package. Holding saves that shipping cost, and it works only when the transfer can arrive before the ship-by date. If it can’t, split the order.

Step 4: Pick, pack, and verify

Once an order is routed, the warehouse that will ship it gets a pick list. A picker collects the items, either one order at a time or in batches, and brings them to a pack station. There, the packer checks the items against the order, chooses a box, adds the packing slip, and prints the label.

Our pick, pack, and ship workflow guide covers picking methods and warehouse layout. The last chance to catch a mis-pick before it ships is the packing bench, where a barcode scan can confirm each item against the order before the label prints. A mis-pick caught there costs a walk back to the shelf. Caught by the buyer, it costs a return and a replacement.

Character (the trading name of Tootonic), a UK retailer of character clothing, recorded inventory locations on paper and in spreadsheets. As the business grew and took on temporary staff, General Manager Emma Hewitt said it “found it very difficult to know where stock was located,” and customer orders were getting mixed up.

After the £53 million business moved warehouse management onto Linnworks, Hewitt said: “it’s much easier to locate all our stock, and we’ve been able to fully automate processes including dispatch.”

Step 5: Hand over to the carrier and confirm shipment

On your own webstore, a shipment is late when it misses the ship date you promised at checkout. On a marketplace, the marketplace decides, and Amazon and eBay check different things.

On Amazon, an order counts as late if you confirm shipment after its ship-by date (the order date plus your handling time). Amazon’s account health target for that late shipment rate is under 4%.

eBay looks for a carrier scan. It counts a shipment as late when tracking from an integrated carrier shows no scan within your handling time and delivery after the estimated date. To hold Top Rated status, a seller needs tracking uploaded within handling time and validated by the carrier on at least 95% of transactions. Late shipments have to stay at five or fewer (or 3% of transactions).

A labeled package hasn’t left until the carrier collects it. So the safest working deadline for an order, whatever the channel, is the last carrier collection or drop-off before its handling time runs out, and picking and packing have to finish before it. On eBay, that collection scan decides whether the shipment counts as late. On Amazon, confirming shipment by the ship-by date keeps the order out of your late shipment rate, but a package that waits for a later collection can still arrive late.

At collection, a manifest (the list of packages and tracking numbers handed to the carrier together) records which packages the carrier took. Each tracking number then has to be sent back to the sales channel that sold the order. Marketplaces check those numbers. Amazon, for example, expects a valid tracking rate (the share of shipments with a tracking number the carrier recognizes) above 95%, so a mistyped or missing tracking number counts against you even when the package arrives on time.

Step 6: Deliver, track, and handle returns

After the first carrier scan, the package’s progress shows in the carrier’s tracking. A shipping notification email with the tracking link lets the buyer check that tracking instead of emailing you to ask where the order is.

Retailers in the 2026 State of Commerce Operations survey work with three carriers on average. Those with several carriers reported fewer service disruptions and more resilience during peak, and retailers reporting fewer disruptions were more likely to use multi-carrier setups with dynamic routing rules.

When a package comes back to the warehouse as a return, someone inspects the item, and it either goes back to a known bin location or gets written off. Until it’s restocked in your inventory records, no sales channel can sell it again. In the State of Commerce Operations survey, returns were among the least automated areas: around a third of retailers still rely heavily on manual work for returns, reporting, and exception handling (orders that need someone to step in, such as oversells and shipping errors).

The Linnworks Returns & Refunds module can restock or scrap a returned item based on instructions you set, and it logs a reason code against every return. If one SKU keeps coming back as “not as described,” the fix belongs in its product listing.

Find the slowest handoff before peak

Before Black Friday on November 27, pull the last 30 days of orders that shipped late on any sales channel. For each order, line up four timestamps:

• Checkout: from the sales channel’s order record
• Arrival in your order system: from its order history
• Label printed: from your order system or shipping software
• First carrier scan: from the carrier’s tracking history

Average each gap across the late orders and start with the longest. If it’s checkout to order system, check how often your order system pulls in orders from that sales channel. The gap from order system to label covers the wait before picking starts as well as the picking and packing, and releasing a second pick wave (a batch of orders sent to the warehouse floor together) before the last collection shortens that wait. A long gap from label to first scan means labeled packages missed a collection, so compare label print times with the carrier’s collection times.

Starting now leaves time to test the change on normal order volume before peak.

To see how Linnworks downloads, routes, and confirms orders across your sales channels, get a demo. Not ready for a demo? The 2026 State of Commerce Operations report covers how 500 US and UK mid-market retailers are handling fulfillment, carriers, and automation, with action points for operations leaders.

FAQs

Do you need a WMS for ecommerce order fulfillment?

Not at every size. A WMS (warehouse management system, software that tracks inventory by bin location and directs picking and packing) becomes necessary once paper records can no longer tell your team where inventory is, which is the point Tootonic reached. Hewitt said a WMS is invaluable “unless you’re a one-man band or only have 10 SKUs.”

Do Fulfillment by Amazon orders count toward your late shipment rate?

No. Amazon’s late shipment rate covers orders you ship yourself (merchant-fulfilled, or FBM). With Fulfillment by Amazon, Amazon ships from its own fulfillment centers and the shipping metrics are its responsibility. Your part is sending inbound shipments to Amazon before your FBA inventory runs out, and making sure units held at Amazon aren’t counted as available on your other sales channels.

Can you fulfill some orders in-house and send others to a 3PL?

Yes. A 3PL is one more warehouse for your routing rules to choose from, so orders can go there by sales channel, destination, or product. The 3PL has to send its inventory counts back to your order system, or your sales channels will keep selling units it no longer holds.

What is an order fulfillment system or solution?

An order fulfillment system is the software that takes each order from your sales channels, reserves inventory, routes the order to a warehouse and carrier, and sends tracking back to the channel. Many sellers use an order management system for this, and add a warehouse management system once picking needs bin-level control. A fulfillment solution can also be a service instead of software, such as a 3PL or FBA.

What is an order fulfillment company?

An order fulfillment company, usually a 3PL, stores your inventory and picks, packs, and ships your orders for a fee. See our rundown of ecommerce fulfillment services to compare providers.