Amazon is the largest e-commerce marketplace in the United States. For sellers managing orders across Amazon, branded storefronts, and other marketplaces, the operational challenge is not listing products. Keeping orders, inventory, and fulfillment synchronized across channels without manual workarounds is where most operations break down.
Third-party sellers now account for 61% of all units sold on the platform, according to Marketplace Pulse. At that scale, manual order downloads and spreadsheet-based inventory tracking cannot keep up. TOMS (Tejas Order Management System) can connect to Amazon Seller Central through Amazon's Selling Partner API (SP-API) to pull orders, sync inventory, push tracking updates, and manage FBM (Fulfilled by Merchant) workflows from a single order management dashboard.
What is the Amazon Selling Partner API, and why does it matter for order management
Amazon's Selling Partner API (SP-API) is the REST-based interface that connects external systems to Seller Central. SP-API replaced the older Marketplace Web Service (MWS) and uses OAuth 2.0 for secure authorization. Full details are available in the SP-API documentation.
For order management, SP-API provides:
- Orders API: Pull order details, including items, quantities, and shipping addresses in real time.
- Feeds API: Push shipping confirmations, tracking numbers, and inventory updates back to Amazon.
- Notifications API: Receive event-based alerts when new orders are placed.
- Inventory API: Read and update stock levels to keep Amazon listings accurate.
TOMS can connect to SP-API to process these data exchanges automatically, eliminating manual downloads and CSV imports.
How TOMS pulls and processes Amazon orders automatically
When a customer places an order on Amazon, TOMS pulls that order into its centralized dashboard alongside orders from every other channel. No manual download or import is required.
The order ingestion flow works in three stages:
Order capture
TOMS can poll the SP-API Orders endpoint at configured intervals or receive event notifications when new orders arrive. Each order imports with full detail: SKUs, quantities, buyer shipping address, shipping service level, and Amazon order ID.
Validation and enrichment
After capture, TOMS validates the order against inventory availability, checks for address issues, and applies any channel-specific rules. Amazon orders follow the same validation pipeline as orders from Shopify, branded storefronts, or other marketplaces.
Routing to fulfillment
TOMS routes validated Amazon orders to the appropriate warehouse or 3PL based on your configured allocation rules.
How TOMS routes Amazon FBM orders across fulfillment locations
Order routing is where TOMS can add the most operational value for Amazon FBM sellers. Instead of defaulting every Amazon order to a single warehouse, TOMS can evaluate each order against its fulfillment network and apply allocation logic automatically.
Proximity-based allocation
TOMS can compare the buyer's shipping address against your registered fulfillment locations and select the closest warehouse with available inventory. Shorter distances mean lower shipping zones and faster delivery, both of which protect your Amazon seller metrics.
Multi-warehouse split handling
When no single location can fulfill the complete order, TOMS can split the order across multiple warehouses. Each split generates a separate fulfillment order with its own pick list, shipping label, and tracking number. All splits map back to the original Amazon order ID, so tracking updates reach the buyer correctly.
Priority and service level routing
Amazon orders with expedited shipping requirements need different handling than standard orders. TOMS can read the shipping service level from the SP-API order data and route expedited orders to locations with carrier pickup schedules that meet the delivery promise.
Channel-specific allocation rules
TOMS can support allocation rules configured per channel. You could reserve a percentage of inventory exclusively for Amazon to protect your seller rating during peak periods, while allowing other channels to draw from a shared pool. Businesses managing complex routing scenarios can learn more in our guide on multi-channel order management.
FBM vs. FBA fulfillment and how TOMS handles each
Amazon sellers choose between two fulfillment models. Understanding how each one works with TOMS determines your integration approach.
FBM (Fulfilled by Merchant) means the seller handles storage, picking, packing, and shipping from their own warehouse or 3PL. FBA (Fulfilled by Amazon) means the seller sends inventory to Amazon's fulfillment centers, and Amazon handles the rest.
The table below compares how TOMS interacts with each model.
| Capability |
FBM with TOMS |
FBA |
| Order routing |
TOMS routes to your warehouse or 3PL |
Amazon handles fulfillment |
| Inventory ownership |
Seller manages stock in its own facilities |
Amazon stores and manages stock |
| Shipping confirmation |
TOMS can push tracking to Seller Central via SP-API |
Amazon generates tracking automatically |
| Returns processing |
TOMS manages returns through your workflow |
Amazon processes returns at its facility |
| Multi-channel use |
The same inventory serves Amazon and other channels |
FBA inventory is Amazon-only unless using MCF |
TOMS provides the most value for FBM sellers and hybrid sellers who use FBA for some SKUs and FBM for others. FBM sellers need an OMS to manage warehouse routing, shipping confirmation, and inventory deduction across channels. FBA-only sellers benefit from TOMS when they also sell through non-Amazon channels and need unified inventory visibility.
End-to-end FBM fulfillment workflow in TOMS
For FBM orders, TOMS can manage the complete lifecycle from order receipt to delivery confirmation:
- Amazon order arrives in TOMS through SP-API.
- TOMS validates payment, checks inventory, and applies routing rules.
- A fulfillment order is created and sent to your warehouse or warehouse management system.
- Warehouse staff pick, pack, and ship the order.
- TOMS captures the tracking number and pushes it back to Amazon.
- Amazon notifies the buyer of shipping and delivery updates.
- After delivery, TOMS can monitor for return requests and initiate the returns workflow if needed.
Each step is automated. FBM sellers processing hundreds or thousands of Amazon orders per day can run the entire flow without touching Seller Central manually.
How TOMS syncs inventory with Amazon in real time
Overselling is the fastest way to damage your Amazon seller metrics. When inventory sells on one channel, but the update does not reach Amazon in time, the result is a cancelled order and a hit to your seller rating.
TOMS can prevent overselling through bidirectional inventory sync:
- Outbound updates to Amazon. When an order ships from any channel, TOMS can deduct inventory and push the updated quantity to Amazon through the Feeds API.
- Inbound updates from Amazon. When Amazon processes an FBA order or receives a return, TOMS can capture the change and update the unified stock count.
- Safety stock buffers. TOMS can support channel-specific safety stock levels to prevent stockouts during high-traffic periods.
Real-time sync matters most for sellers operating across Amazon, Shopify, and D2C storefronts simultaneously. For more on unified inventory strategies, see our guide on order management best practices.
How TOMS manages FBM returns and exchanges from Amazon
FBM sellers are responsible for processing their own returns. Amazon's return policy applies, but the seller handles receipt, inspection, restocking, and refund processing. Without an OMS managing this flow, returns create inventory discrepancies and delayed refunds that hurt seller metrics.
TOMS can handle FBM returns through a structured workflow:
- Return authorization. When a buyer initiates a return through Amazon, TOMS can receive the return request and create a return merchandise authorization (RMA) with the reason code and item details.
- Receipt and inspection. After the item arrives at your warehouse, staff logs the return in TOMS. The system can capture the item condition and determine whether it qualifies for restocking or needs to be flagged as damaged.
- Inventory re-addition. Restockable items can be added back to available inventory automatically. TOMS can push the updated quantity to Amazon and all other connected channels so stock levels stay accurate.
- Refund processing. TOMS can trigger the refund through the appropriate payment channel based on the return reason and your configured refund rules.
For sellers processing high return volumes, TOMS can provide reporting on return rates by SKU, reason code frequency, and restocking percentages. Patterns in return data often reveal product quality issues or listing inaccuracies that can be fixed to reduce future returns. Businesses that follow order management best practices track return metrics alongside fulfillment KPIs.
How to connect TOMS to Amazon Seller Central
Setting up the TOMS-to-Amazon integration follows a structured process. Here are the key steps.
- Register as an SP-API developer. Create an Amazon developer account and obtain API credentials.
- Authorize TOMS. Complete the OAuth 2.0 flow so TOMS can read orders and push updates on your behalf.
- Map product identifiers. Align Amazon ASINs and SKUs with your TOMS product catalog.
- Configure inventory sync. Set sync frequency, safety stock buffers, and channel-specific allocation rules.
- Test with live orders. Process a batch of real orders, verify inventory deductions, and confirm tracking pushes back correctly.
- Go live and monitor. Enable full automation and track API response times and error rates through TOMS dashboards.
Challenges in Amazon OMS integration and how to solve them
Connecting an OMS to Amazon introduces specific operational challenges. Here are the most common issues and how to address them.
API rate limits and throttling
Amazon enforces rate limits on SP-API calls. High-volume sellers may hit throttling during peak periods.
TOMS can use efficient polling intervals and the Notifications API for event-driven updates, reducing unnecessary API calls.
SKU mapping across channels
Product identifiers differ between Amazon (ASIN), Shopify (variant ID), and your internal SKUs.
TOMS maintains a unified product catalog that maps each channel's identifier to a single master SKU, preventing duplicate listings and inventory mismatches.
Delayed inventory updates are causing oversells
Batch sync intervals can leave a gap where inventory sells on one channel but is not yet deducted on another.
TOMS can push updates in near real time and supports safety stock buffers. For sellers using a warehouse management system, real-time WMS-to-OMS feeds can further reduce the gap.
Streamline your Amazon fulfillment with TOMS
Managing Amazon orders alongside other sales channels requires an OMS built for multi-channel automation. We can connect TOMS to Amazon Seller Central, configure SP-API integration, and set up inventory sync rules that keep your listings accurate across every channel. TOMS integrates with TWMS for warehouse execution and supports 100+ channels worldwide.
Book a demo with Tejas Software to see how we can help.
FAQ's
How does TOMS integrate with Amazon Seller Central to pull and process orders automatically?
TOMS can connect through Amazon's SP-API to pull orders in real time. Each order imports with full details and enters the same validation and routing pipeline used for all other channels.
What is the difference between FBM and FBA fulfillment, and how does TOMS handle each?
FBM means the seller handles fulfillment. FBA means Amazon fulfills. TOMS can manage the full FBM workflow and provide unified inventory visibility for sellers using both models.
How does TOMS sync inventory levels with Amazon in real time to prevent overselling?
TOMS can push inventory updates to Amazon through the Feeds API whenever stock changes on any channel. Safety stock buffers and near real-time sync help prevent overselling.
How are Amazon shipping confirmation and tracking numbers sent back to Seller Central through TOMS?
After the warehouse completes shipment, TOMS can capture the tracking number and push it to Amazon through SP-API automatically. No manual upload is required.
Can TOMS manage orders from Amazon alongside other channels like Shopify or a branded storefront in one view?
Yes. TOMS consolidates orders from Amazon, Shopify, branded storefronts, and 100+ other channels into a single dashboard with unified inventory and fulfillment workflows.
What are the key steps to connect TOMS to Amazon Seller Central for the first time?
Register as an SP-API developer, authorize TOMS through OAuth, map product identifiers, configure inventory sync rules, test with live orders, and go live with monitoring enabled.
