The FBA Inbound Process Explained
Sending stock to Amazon FBA is one of the most important processes you'll learn as an Amazon seller. Get it right and your products go live within days. Get it wrong and you'll face delays, rejected shipments, and compliance fees that eat into your margins.
The process breaks down into a clear sequence: source your products, prepare them to Amazon's standards, create a shipping plan in Seller Central, pack and label your boxes, choose a carrier, and ship to the assigned fulfilment centre. Each step has specific requirements that Amazon enforces strictly.
This guide walks through every stage in detail, whether you're shipping your very first box of 50 units or scaling to thousands. We'll also cover where a prep centre fits in and how it can remove most of the complexity from your side.
Before You Ship: What You Need Ready
Before you touch Seller Central's shipping workflow, you need a few things in place. Missing any of these will stall your shipment.
Active Seller Central Account
You need an Amazon Seller Central account with FBA enabled. If you're on an Individual plan, you can still use FBA, but a Professional plan (check current pricing) unlocks bulk listing tools and the full shipping workflow. Make sure your account is in good standing with no suspensions or restrictions.
Product Listings Created
Every product you want to send must have a listing on Amazon. If you're selling an existing product (wholesale or arbitrage), you match to the existing ASIN. If you're launching a private label product, you create a new listing first. Each listing must be converted to "Fulfilled by Amazon" — you do this in the inventory management section of Seller Central.
FNSKU Labels
Once your listing is set to FBA, Amazon generates an FNSKU barcode for each product. This unique barcode ties the item to your seller account. You'll need to print these labels and apply them to every single unit before it reaches Amazon. The FNSKU must cover any existing barcodes on the product packaging. If you're using a prep centre, they handle this labelling for you.
Prep Materials
Depending on your product category, you may need poly bags (with suffocation warnings for bags over 5 inches), bubble wrap for fragile items, "Sold as Set" stickers for bundles, and shipping boxes that meet Amazon's size requirements. Again, a prep centre stocks all of these materials as standard.
Step-by-Step: Creating Your FBA Shipment
Here's the exact process for getting your inventory from your hands (or your prep centre's hands) into Amazon's warehouses.
Create a Shipping Plan in Seller Central
Go to Inventory > Manage FBA Shipments > Create New Shipping Plan. Select the products you want to send and enter the quantities. Amazon uses this information to decide which fulfilment centre(s) your stock should go to. You'll set your "ship from" address — this is either your address or your prep centre's address.
Confirm Prep and Labelling Requirements
Amazon will tell you what prep each item needs (poly bagging, bubble wrap, etc.) and whether you're labelling the items yourself or paying Amazon to do it. Always choose "Merchant" for labelling — Amazon charges per unit for their labelling service, and it's significantly more expensive than doing it yourself or using a prep centre. This screen also shows any category-specific prep requirements.
Review Shipment Splits
Amazon may split your inventory across multiple fulfilment centres. This is normal — Amazon distributes stock to optimise delivery speed for customers. You'll see which items go to which warehouse. You can use Amazon's "Inventory Placement Service" (for a fee) to send everything to one centre, but most sellers accept the splits as it's more cost-effective overall.
Print FNSKU Labels
Download and print the FNSKU labels for every unit. Use thermal labels (recommended) or standard A4 sheets with adhesive labels. Each label must be scannable — no smudging, no partial prints. Apply one FNSKU label per unit, covering the existing manufacturer barcode. If you're using Precision Prep & Fulfilment, you skip this step entirely — they print and apply all labels for you.
Prep and Pack Your Products
Apply any required prep (poly bags, bubble wrap, suffocation warnings). Then pack your units into shipping boxes. Amazon has strict box requirements: maximum 50 lbs (23 kg) per box, no dimension over 25 inches (63.5 cm) for standard-size items. Use sturdy corrugated boxes — no thin or damaged cardboard. Fill any empty space with dunnage (packing paper, air pillows) to prevent items shifting in transit.
Print and Apply Box Labels
Once your boxes are packed, go back to Seller Central and enter the box contents (how many of each item per box). Amazon generates unique box labels (called FBA Box ID labels) for each box. Print these and stick one on the outside of each box. These labels tell Amazon's warehouse staff exactly what's inside without opening the box. Every box must have its own unique label — never photocopy or reuse labels.
Choose Your Carrier and Ship
Select a carrier for delivery. Amazon offers partnered carrier rates (usually through Parcelforce or palletised carriers for larger shipments) which are often the cheapest option. You can also use your own carrier. For small parcel deliveries, you'll get a shipping label to print. For palletised shipments, you'll book a collection. Once shipped, enter the tracking information in Seller Central.
Tip: Always double-check your box contents match what you entered in Seller Central. Discrepancies trigger investigations that can delay your inventory going live by weeks. If you regularly ship large volumes, using a prep centre like Precision eliminates this risk — they verify counts at every stage.
Amazon's Box and Packing Requirements
Amazon is very particular about how boxes are packed. Failing to meet these requirements can result in your shipment being refused at the warehouse door, returned to you at your cost, or incurring non-compliance fees. Here are the key rules:
Box Size and Weight
Standard-size boxes must not exceed 25 inches on any side and must weigh no more than 50 lbs (23 kg). If a single item weighs over 50 lbs, it ships as an individual unit with a "Team Lift" label. Boxes between 50-100 lbs require a "Team Lift" label. Over 100 lbs requires a "Mechanical Lift" label and palletisation.
Box Quality
Use new or like-new corrugated cardboard boxes. No thin boxes, no boxes with holes or tears, and no boxes that have been heavily taped over. Amazon's conveyor systems are rough — weak boxes get crushed and your inventory arrives damaged. This reflects poorly on your account.
Packing Inside the Box
Items must not move freely inside the box. Fill all empty space with clean dunnage — packing paper, air pillows, or foam. Never use loose fill peanuts (Amazon bans them). Items should be packed tightly enough that the box sides don't bulge or cave in. Each item must have its FNSKU label facing outward and scannable without unpacking.
Box Labels
Every box gets a unique FBA Box ID label from Seller Central. Place it on a flat surface of the box (not on a seam or edge). The label must be scannable — don't fold it around corners. Remove or cover any old shipping labels from previous use. One label per box, clearly visible.
Palletised Shipments
If you're sending more than a few boxes, palletising is often required. Standard UK pallets (120cm x 100cm) or Euro pallets (120cm x 80cm) are accepted. Stack boxes evenly, don't overhang the pallet edge, and wrap the pallet securely with stretch wrap. Maximum pallet height including the pallet itself is 180cm. Each pallet needs four pallet labels — one on each side.
Common Mistakes That Delay Your Shipment
Even experienced sellers trip up on these. Avoiding them saves you time, money, and stress.
Incorrect FNSKU Labels
Printing the wrong FNSKU, applying labels upside down, or not covering the manufacturer barcode are the most common errors. If Amazon scans the wrong barcode, your inventory gets mixed with another seller's stock (called "commingling"), leading to customer complaints and potential account issues.
Box Content Mismatch
What you tell Seller Central is in the box must match what's actually in the box. If you say there are 24 units inside and there are 22, Amazon flags this. Repeated mismatches can result in your account losing the ability to use "less-than-truckload" shipments and having to provide individual item scans.
Missing Prep
Sending items that need poly bagging without bags, or fragile items without bubble wrap, results in non-compliance charges. Amazon charges per unit for prep they have to do themselves, and it's far more expensive than doing it correctly upfront.
Shipping to the Wrong Fulfilment Centre
Each shipment in Seller Central is assigned to a specific fulfilment centre. Sending boxes to the wrong one means Amazon rejects the delivery and you pay for return shipping. Always check the destination address carefully before shipping.
Expired Shipping Plans
Shipping plans have an expiration period. If you don't ship within that window, you'll need to create a new plan. Don't create plans until you're ready to ship within a reasonable timeframe.
Why sellers use a prep centre: Every mistake listed above is eliminated when you use a professional prep centre. At Precision Prep & Fulfilment, quality checks are built into every stage — from receiving and inspection through to final box labelling and shipping. Your inventory arrives at Amazon compliant, accurate, and on time. Read our comparison of prep centre vs DIY for more detail.
Choosing a Carrier: Your Options in the UK
How you get your boxes to Amazon depends on the size of your shipment and your budget.
Amazon Partnered Carriers
Amazon negotiates discounted rates with carriers like Parcelforce and various pallet networks. These "partnered carrier" rates are usually the cheapest option, especially for small parcel shipments. You book and pay directly through Seller Central, and tracking is automatically linked to your shipment. For most UK sellers sending a few boxes at a time, this is the easiest and cheapest route.
Your Own Courier
If you have a business account with a courier (DPD, Hermes/Evri, Royal Mail, UPS, FedEx), you can use your own carrier. This gives you more control over collection times and delivery speed, but you'll need to manually enter tracking numbers in Seller Central. It can be cheaper for large-volume sellers with negotiated commercial rates.
Pallet Couriers
For larger shipments (typically 4+ boxes), palletised delivery through a freight carrier is more cost-effective than sending individual parcels. Companies like Palletways, Palletline, and TNT handle pallet deliveries to Amazon's fulfilment centres across the UK. Your prep centre can arrange this for you — Precision handles all pallet bookings and logistics as part of the service.
Collection Services
Some prep centres (including Precision) offer a nationwide collection service. If your supplier is delivering stock to you first, or if you're buying from local wholesalers, the prep centre can arrange collection from your supplier or your home, saving you the hassle of shipping it to them yourself. Get in touch for details.
After You Ship: What Happens Next
Once your shipment is on its way, here's the timeline you can expect.
Receiving at the Fulfilment Centre
After your carrier delivers the boxes, Amazon's warehouse team checks them in. The time for Amazon to receive and stow your inventory varies depending on their workload and seasonality (peak times can take longer). You'll see the status update in Seller Central from "Shipped" to "Delivered" to "Checked In" to "Receiving" and finally "Closed" when all units are stowed.
Inventory Goes Live
Once Amazon finishes receiving and stowing your inventory, the units become available for purchase. Your listing shows as "In Stock" and customers can order. If you're already running PPC campaigns, your ads will start appearing as soon as stock is live.
Discrepancies
Sometimes Amazon's received count doesn't match what you sent. If units are missing, you can open a reconciliation case in Seller Central. Amazon investigates and either finds the missing units or reimburses you. This is why accurate box content information is critical — it's your proof of what you sent.
Pro tip: Keep a record of every shipment — what you sent, how many units per box, the total weight, and photos of the packed boxes. This documentation is invaluable if you ever need to dispute a discrepancy with Amazon. Precision's client portal provides digital records of every shipment they process, giving you a complete audit trail.
How a Prep Centre Simplifies the Entire Process
If the process above sounds like a lot of work, that's because it is. This is exactly why most serious Amazon sellers in the UK use a prep centre. Here's how the workflow changes when you partner with Precision Prep & Fulfilment:
Your suppliers ship directly to Precision's warehouse in Atherstone. You give them the prep centre address and your stock arrives without you ever touching it.
Precision receives and inspects everything. They check quantities, note any damage, and log it all into their system. You get notified when stock arrives.
They prep every unit to Amazon's exact standards. FNSKU labels printed and applied, poly bagging done, bundles assembled, boxes packed correctly with proper dunnage. No compliance issues, no rejected shipments.
They create the shipping plan and ship to Amazon. They handle the Seller Central workflow, book the carrier, apply box labels, and track the delivery until it's checked in at the fulfilment centre.
You focus on selling. While your prep centre handles the logistics, you spend your time on sourcing new products, optimising listings, running PPC campaigns, and growing your business.
The cost? Standard prep starts at just 45p per unit, including everything from receiving through to shipping. For most sellers, this is cheaper than DIY when you factor in time, materials, and the risk of errors. See our full cost breakdown for the numbers.