An Amazon fulfillment center code is a short identifier — commonly four characters, three letters plus a digit, such as MKC6 — that Amazon assigns to one of its buildings. Amazon’s own published API model defines the field bluntly: “An Amazon fulfillment center identifier created by Amazon.” (Selling Partner API, Fulfillment Inbound v0 model, published by Amazon in its amzn/selling-partner-api-models repository; checked 2026-08-20.) Two consequences follow, and they are the whole point of this page. You can read a code well enough to know roughly which metro area a shipment went to. You cannot use a code — or any third-party address list built from codes — to decide where to ship, because the only valid destination is the one your own shipping plan hands you at the moment you build it.
This guide covers what the code structure actually encodes, the facility types sitting behind those codes, what Amazon publishes versus what circulates unofficially, and the four situations where a seller genuinely needs the code. It does not contain a “complete list of Amazon warehouse addresses,” and the last section explains why every list that claims to be one is wrong somewhere.
How to Read a Fulfillment Center Code
Start with what is verifiable. Amazon’s public Selling Partner API models — the JSON files Amazon itself publishes for developers — use real-shaped values for the destination field. The Fulfillment Inbound v0 model shows a worked example response containing "DestinationFulfillmentCenterId": "MKC6", and the newer 2024-03-20 inbound model uses the placeholder ABC1 for its warehouseId field (both checked 2026-08-20). That gives you the shape: three letters, then a digit.
The three letters correspond to a nearby airport or metro area, and the digit distinguishes buildings within that same area. Amazon does not publish a document explaining this convention — see the next section for the pages checked. It is a pattern you can confirm yourself in seconds rather than a rule you should quote as official: take the letters from a code your own account produced, look them up as an airport code, and see whether the state your report shows matches. When it does, you have a metro-level read on where that shipment went, which is usually all a seller needs.
What the code will not tell you matters more:
| The code tells you | The code does not tell you |
|---|---|
| A metro-level hint from the three letters | The street address |
| That two shipments went to different buildings | Whether the building is a fulfillment center at all |
| A stable label for reconciling reports | Whether it still accepts seller inbound freight today |
| A value to quote to a carrier alongside the address | Anything about size, speed, or handling quality |
The digit is a sequence marker within a metro, not a ranking. A higher digit does not mean a newer, larger or faster building in anything Amazon publishes, and nothing in the code indicates capacity, category focus, or how quickly that building receives.
The Facility Types Behind the Codes
Amazon does publish facility type definitions, on its corporate site. These are the categories, quoted verbatim from aboutamazon.com/workplace/facilities (checked 2026-08-20):
| Facility type | Amazon’s own description |
|---|---|
| Sortable fulfillment center | “In these buildings, Amazon employees pick, pack, and ship customer orders such as books, toys, and housewares.” |
| Non-sortable fulfillment center | “In these centers, associates pick, pack, and ship bulky or larger-sized customer items such as patio furniture, outdoor equipment, or rugs.” |
| Sortation centers | “At sortation centers, associates sort customer orders by final destination and consolidate them onto trucks for faster delivery.” |
| Receive centers | “Amazon’s receive centers support customer fulfillment by taking in large orders of the types of inventory that we expect to quickly sell and allocating it to fulfillment centers within the network.” |
| Delivery stations | “In these buildings, customer orders are prepared for last-mile delivery to customers.” |
Only one of these families is a destination your FBA shipment will be routed to by the workflow, and it is whichever building the plan names — Amazon’s inbound API calls that value a fulfillment center identifier or a warehouse ID. Sortation centers and delivery stations sit downstream of the fulfillment center, on the customer-order side; they never take seller inbound freight.
The seller-community shorthand you will see for the upstream buildings — “IXD” for inbound cross-dock, “RC” for receive center — does not appear in Amazon’s published facility list. Amazon’s published term for that function is receive centers, described above. Treat the abbreviations as forum vocabulary, not as labels you can rely on.
Here is the trap. Amazon publishes no mapping from a code to a facility type. Nothing in MKC6 says “sortable fulfillment center”, and nothing in a delivery station’s code says “do not send pallets here.” Sellers who ship to an address they found in a directory can therefore land freight at a building that has no seller-inbound dock at all — and the carrier discovers it at the gate, not before.
What Amazon Publishes, and What It Does Not
Published and readable without a seller account, as of 2026-08-20:
- The facility type definitions above.
- The scale, in round terms: “Our network includes hundreds of fulfillment centers worldwide” (
sell.amazon.com/fulfillment-by-amazon, checked 2026-08-20). No count of buildings, no list. - The process: “Transport your products to an Amazon fulfillment center using the Send to Amazon workflow.” (same page).
- The data contract, in the Selling Partner API models — including the destination structure quoted in the next section.
Behind a seller login: Seller Central’s help hub carries an article titled “Amazon fulfillment centers in the US” (help node 201811680). We could not read it. Requests on 2026-08-20 to sellercentral.amazon.com/help/hub/reference/external/201811680?locale=en-US, sellercentral.amazon.com/gp/help/external/G201811680?language=en_US and sellercentral.amazon.com/gp/help/201811680 returned Seller Central’s application shell or a sign-in redirect rather than article text. So this page makes no claim about what that article contains — if you have an account, read it there and treat it as the authority over anything below.
Not found on any public Amazon page we checked: an explanation of the code format, and a complete address-level directory of fulfillment centers outside the seller workflow. Pages checked on 2026-08-20 were aboutamazon.com/workplace/facilities, aboutamazon.com/amazon-fulfillment/our-fulfillment-centers, sell.amazon.com/fulfillment-by-amazon, supplychain.amazon.com/blog/how-to-send-inventory-to-amazon-fulfillment-centers, and the three Seller Central URLs above. The corporate facilities pages describe types and give regional colour only; none carries a code, a map, or an address table.
That is the honest state of it: “we did not find Amazon publishing a complete public list”, not “Amazon has confirmed there is none.” The distinction matters, because the third-party directories that fill the gap are compiled by freight forwarders, prep centers and content sites from shipping labels sellers post — useful as background reading, never as a shipping instruction. They rot silently. Buildings open, close, change function and change the freight they accept, and nobody edits a blog table when that happens. A directory row that was accurate last year and wrong today looks exactly the same.
The Only Address That Counts
Amazon’s own data model settles this argument better than any advice could. In the 2024-03-20 Fulfillment Inbound model, the shipment destination object is described as “The Amazon fulfillment center address and warehouse ID”, and its two key fields read (verbatim, checked 2026-08-20):
address— “The address the shipment should be sent to. This can be empty if the destination type isAMAZON_OPTIMIZED.”warehouseId— “The warehouse that the shipment should be sent to. This can be empty if the destination type isAMAZON_OPTIMIZED.”destinationType— “The type of destination for this shipment. Possible values:AMAZON_OPTIMIZED,AMAZON_WAREHOUSE.”
Read those three lines together and the practical rule writes itself. Until a placement is settled, there may be no warehouse and no address at all — the fields are legitimately empty. There is nothing to look up in advance, because the value does not exist yet. What you choose between is not warehouses but placement options: Amazon defines one as “A placement option represents the shipment splits and destinations of SKUs.” You accept a split-and-destination package, and the addresses fall out of that decision. If you are weighing those packages against each other, the fee arithmetic is covered in our guide to shipping FBA inventory to one warehouse.
So the discipline is simple, and it is the single most valuable line on this page: the shipping labels, the bill of lading and the carrier appointment must all take the address from the plan you just created, in that session, for that shipment. Not from a saved address book, not from last quarter’s shipment, not from a directory. For LTL and FTL freight, the code and address you feed into the appointment booking come from the same place — see how Amazon Carrier Central appointments get booked.
Four Times a Seller Genuinely Needs the Code
1. Booking a delivery appointment. Freight carriers ask for the destination code alongside the address, and the pairing is what stops a driver from arriving at the right city and the wrong building. Copy both from the shipment record.
2. Reading where inventory landed. The 2024-03-20 model returns a destination region carrying countryCode, state and warehouseId — so the state, not the street, is the level at which Amazon exposes placement. That is enough to reason about coverage: units concentrated in two states will show different delivery promises than units spread across six.
3. Reconciling receipts split by destination. When one plan splits into several shipments, each is received separately and each can go wrong separately. Reconciling by destination is how you find the shipment that closed short rather than noticing an aggregate number that looks roughly right. That reconciliation is the front half of a reimbursement case — our FBA reimbursement guide covers which discrepancy types are claimable and the windows that apply, and ReimburseOps is one of the tools that audits reports for those discrepancies on a flat subscription rather than a share of recoveries.
4. Explaining an odd routing. A shipment that went to an unexpected metro is not usually an error; it is Amazon balancing its network against forecast demand. The code is the first clue in that investigation, and shipment status is the second — see how to track FBA shipments end to end.
Common Mistakes
Shipping to an address found in a directory. The most expensive one. Freight arrives at a building that is not expecting it, without a valid appointment, and becomes the carrier’s problem and then yours.
Assuming one metro means one building. Two codes sharing the same three letters share a metro area and nothing else operationally — separate buildings, separate docks, separate appointments. Same-metro codes do not mean you can consolidate two shipments into one delivery.
Assuming a SKU keeps its destination. The destination is computed per plan against current network state. Last month’s code for the same SKU carries no authority this month.
Trying to choose a fulfillment center. Sellers can influence how many destinations a shipment splits into, and pay accordingly. Choosing a specific building by code is not an option Amazon exposes anywhere in the workflow or the API.
Confusing AWD destinations with FBA fulfillment centers. Amazon Warehousing and Distribution is a separate upstream storage service with its own destinations and its own rate card; see the Amazon AWD guide before assuming a code you saw there behaves like an FBA fulfillment center code.
Frequently Asked Questions
What does an Amazon fulfillment center code mean?
It is an identifier Amazon assigns to one of its buildings — commonly three letters plus a digit, such as MKC6. Amazon’s API model describes the field as “An Amazon fulfillment center identifier created by Amazon” (checked 2026-08-20). The letters correspond to a nearby airport or metro area and the digit distinguishes buildings within it, though Amazon does not publish this convention in any page we could find.
Does Amazon publish a list of all FBA warehouse locations?
Amazon’s corporate site publishes facility types and says the network includes “hundreds of fulfillment centers worldwide”, but we found no public, address-level directory on Amazon’s own domains as of 2026-08-20. Seller Central carries a help article titled “Amazon fulfillment centers in the US” that requires a seller login; if you have an account, that is the source to trust over any third-party table.
Can I choose which fulfillment center receives my inventory?
No. You choose a placement option — Amazon’s own definition is “A placement option represents the shipment splits and destinations of SKUs” — and the destinations follow from it. There is no mechanism, in the workflow or the API, for naming a building.
Are the fulfillment center address lists on logistics blogs safe to use?
Use them for background only. They are compiled by third parties from labels sellers post, they carry no Amazon backing, and no one updates them when a building changes function or closes. Shipping to an address from such a list, rather than from your current shipping plan, is the single most common way freight ends up at the wrong dock.
Why did my shipment get split across several fulfillment centers?
Because the placement option you accepted specified that split. Amazon distributes units to position them nearer to forecast demand; multiple destinations is the default outcome, and reducing them to one is a paid option rather than a setting.
The Bottom Line
Read the code for orientation, never for instruction. Three letters give you a metro, the digit gives you a building within it, and Amazon’s own API tells you the rest: the identifier is created by Amazon, the address arrives with the placement decision, and both fields are legitimately empty until that decision is made. Any list that offers you those values in advance is offering something Amazon’s own system does not have yet — which is the clearest possible sign to close the tab and open your shipping plan instead.