Quick answer: An Amazon marketplace integration connects your Amazon Seller Central account to your own store, inventory system or ERP so stock levels, listings and orders stay in sync automatically. Smaller sellers usually start with a plugin or app for their store platform. Growing sellers with several channels often use a multichannel listing tool. Businesses with complex catalogs or an existing ERP may need custom integration through Amazon’s APIs. Whatever you choose, decide which system is the single source of truth for stock, and test overselling scenarios before going live.
Why integration matters
Selling on Amazon alongside your own website can add a lot of sales. It also doubles the admin if the two are not connected. Without integration, someone has to:
- Update stock on Amazon every time something sells on your site, and vice versa
- Copy Amazon orders into your fulfillment, accounting or shipping systems
- Keep prices, titles and images consistent across channels
- Upload tracking numbers back to Amazon
Manual updates are slow and error-prone. The biggest risk is overselling: an item sells on your site, the Amazon listing still shows it in stock, and a second customer buys something you cannot ship. On Amazon, cancellations and late shipments hurt your seller metrics, and poor metrics can lead to restrictions on your account.
What needs to sync
Inventory
Stock levels are the most important thing to keep in sync. Every sale on any channel should reduce available stock everywhere, ideally within minutes. Our guide to inventory sync with APIs covers the general patterns.
Orders
Amazon orders need to reach whoever packs and ships them, unless Amazon fulfills them for you. They also need to reach accounting so revenue and fees are recorded correctly.
Listings and product data
Titles, descriptions, images, prices and attributes. Amazon has its own catalog rules and category requirements, so product data often needs mapping rather than a straight copy.
Shipping and tracking
For orders you fulfill yourself, tracking numbers and ship confirmations must go back to Amazon on time.
Pricing
Some sellers keep prices identical across channels. Others price differently on Amazon to cover referral fees. Either way, price changes should flow from one place.
FBA vs FBM: how fulfillment affects integration
Fulfilled by Amazon (FBA): You send stock to Amazon’s warehouses, and Amazon picks, packs and ships. Your integration mainly needs to track how much stock sits at Amazon and keep it separate from stock in your own warehouse. Some sellers also use Amazon’s Multi-Channel Fulfillment service to ship orders from their own website using FBA stock.
Fulfilled by Merchant (FBM): You ship Amazon orders yourself. Your integration needs to pull orders quickly, push them into your shipping process and send tracking back.
Many sellers use both, which makes clear stock rules even more important.
Integration options
Store plugins and apps
Most ecommerce platforms have Amazon connectors:
- WooCommerce: Several plugins list products on Amazon, import orders and sync stock. They suit small to medium catalogs where WooCommerce is the main system.
- Shopify: Amazon sales channel apps and third-party connectors handle listing and order import.
- BigCommerce and Magento: Both have native or third-party Amazon integrations.
Good for: Single store plus Amazon, simple catalogs, limited budget.
Watch for: Limits on variations, bundles or multiple warehouses, and how quickly stock updates run. Check reviews from sellers with similar volume.
Multichannel listing tools
Dedicated multichannel tools sit between your channels: your website, Amazon, eBay, Etsy and others. They hold a central product catalog and stock count and push changes out to each channel.
Good for: Sellers on several marketplaces, growing order volume, teams that want one dashboard.
Watch for: Monthly fees that scale with orders or SKUs, and the need to keep product data clean in yet another system.
Inventory management and ERP systems
If you already run an inventory system or ERP, check whether it has an Amazon connector. Making that system the source of truth for stock often works best for businesses with physical warehouses, wholesale channels or manufacturing. Our article on ERP integration covers the trade-offs.
Custom integration
When off-the-shelf tools do not fit, a custom integration talks to Amazon’s APIs directly. Reasons to go custom include unusual product structures, complex bundles, a homegrown order system, strict accounting requirements or very high volume.
Amazon has long offered Marketplace Web Service (MWS) for this, and has recently introduced the Selling Partner API as its newer, REST-based successor. Any new custom project should plan around the Selling Partner API, since Amazon is moving developers in that direction. Custom work costs more up front but can remove recurring fees and fit your process exactly.
Choosing a source of truth
The most important design decision is which system owns stock. Common choices:
- Your online store: Simple for small sellers whose website is the main channel.
- A multichannel tool: Good when several marketplaces matter equally.
- Your ERP or inventory system: Best when stock also moves through wholesale, retail or production.
Everything else should read stock from that system and report sales back to it. Two systems both trying to own stock is a common cause of overselling.
Practical safeguards
Stock buffers
Set a buffer so a channel shows slightly less stock than you have. If you have 5 units, show 3 on Amazon. It reduces the chance of overselling during sync delays, at the cost of occasionally under-listing.
Sync frequency
Check how often your tool updates Amazon. Every few minutes is good. Once an hour may be too slow for fast-moving products.
SKU discipline
Use the same SKU for the same product everywhere. Mismatched SKUs are one of the most common reasons integrations fail quietly.
Bundles and variations
If you sell bundles, make sure the integration reduces stock of each component. Variations like size and color need to map cleanly to Amazon’s parent and child listings. Our guide to WooCommerce product variations covers structuring variations on the store side.
Monitoring and alerts
Set up alerts for failed syncs, orders that did not import and listings with errors. A daily stock comparison report catches drift before it causes problems.
Accounting and fees
Amazon deducts referral fees, fulfillment fees and other charges before paying you, and settlement reports group many orders together. That makes it hard to match payouts to sales in your books. Connecting Amazon to your accounting system, directly or through a connector, saves hours each month. Our article on ecommerce accounting integration explains how to record marketplace sales and fees cleanly.
Rollout checklist
- Clean up product data and SKUs.
- Decide the source of truth for stock.
- Choose the integration approach.
- Test with a small set of products first.
- Simulate simultaneous orders on both channels to check overselling protection.
- Test returns and cancellations.
- Confirm tracking numbers upload correctly for FBM orders.
- Expand to the full catalog and monitor closely for the first few weeks.
FAQ
Can WooCommerce sync with Amazon?
Yes. Several plugins handle listing, stock and order sync. Test with your catalog size and product types before committing.
Do I need a multichannel tool if I only sell on my site and Amazon?
Not always. A good store plugin may be enough. Multichannel tools become more valuable as you add marketplaces.
How fast should stock sync?
As close to real time as practical. Within a few minutes is a good target for most sellers.
Is a custom integration worth it?
It can be when your processes are unusual, your volume is high, or subscription fees across tools add up. Get a clear estimate and compare it with several years of tool costs.
Next step
Map where your stock, orders and product data live today, and decide which system should own each. That map makes choosing a tool much easier. If you also plan to expand abroad, read our guide on how to sell internationally online.
If you would like help connecting Amazon to your store, inventory or accounting, see our Turn visitors into customers services.
