Fulfillment guide for selling on Amazon and other marketplaces

Last week, we discussed fulfillment and TikTok Shop, as well as how to adapt your sales to social commerce. As you may have seen, nowadays, eCommerce is rapidly evolving, reaching customers across multiple marketplaces like Amazon, eBay, Walmart, and Etsy.

That is why your eCommerce plan needs more than a strategy for its growth. Mostly because managing inventory, shipping, and customer expectations across these platforms can quickly become overwhelming without an efficient fulfillment process in place. 

As a fulfillment center in Mexico, we can tell you that understanding the nuances of fulfillment is crucial to ensuring customer satisfaction, optimizing operations, and maintaining a competitive edge.

This guide breaks down everything you need to know about fulfillment to succeed in marketplaces, from choosing between Fulfillment by Amazon (FBA), Walmart, or eBay to navigating the unique requirements of various online marketplaces.

What is fulfillment in eCommerce?

Fulfillment in eCommerce refers to the entire process of receiving, processing, packaging, and delivering a customer's order. It begins when a customer places an order through an online marketplace or website and continues until the product reaches their doorstep. 

In practice, eCommerce fulfillment can be handled in various ways. Some sellers manage the process themselves, storing products in a home or warehouse, packing them manually, and shipping them using postal services. Others outsource to third-party logistics (3PL) providers or use built-in fulfillment services offered by platforms like Amazon (FBA), which handle almost every step on behalf of the seller.

Marketplace overview and fulfillment expectations

Each online marketplace has its own set of rules, customer expectations, and fulfillment requirements. Understanding how fulfillment works across different platforms is essential for optimizing operations, maintaining good standing with marketplace policies, and delivering a seamless customer experience. Hereunder, we develop the main elements of each platform.

1.- Amazon

Amazon is known for its Prime-level delivery standards and strict performance metrics. Sellers on Amazon can choose between Fulfillment by Amazon (FBA) and Fulfilled by Merchant (FBM), each with distinct implications for logistics and customer experience.

FBA (Fulfillment by Amazon)

With FBA, sellers ship their products to Amazon's fulfillment centers, and Amazon takes over storage, packing, shipping, customer service, and returns. This method allows sellers to offer Prime-eligible products, which can significantly increase visibility and sales. 

However, FBA involves storage, fulfillment fees, and strict inventory requirements. It is best suited for sellers who want to scale quickly and don't want to manage shipping logistics themselves.

FBM (Fulfilled by Merchant)

FBM allows sellers to maintain control over the fulfillment process, either by handling it themselves or using a third-party logistics provider. While it gives sellers more flexibility and can be more cost-effective for certain product types, it also comes with the responsibility to meet Amazon’s high standards for on-time delivery, order accuracy, and customer service.

2.- eBay

eBay operates on a more traditional marketplace model, where most sellers handle their own fulfillment. Although eBay does not have a proprietary fulfillment network like Amazon’s FBA, it has introduced programs like eBay Guaranteed Delivery to encourage faster shipping.

Sellers are expected to clearly communicate handling times, shipping costs, and return policies. High-performing sellers often use shipping software or 3PLs to streamline their operations. While fulfillment flexibility is high on eBay, customer satisfaction depends heavily on prompt delivery, clear communication, and accurate listings.

3.- Walmart Marketplace

Walmart Marketplace is rapidly growing and attracts professional sellers with competitive pricing and reliable fulfillment practices. Walmart offers its own fulfillment solution, Walmart Fulfillment Services (WFS), which operates similarly to Amazon’s FBA.

WFS allows sellers to leverage Walmart’s vast logistics network, offering fast shipping and increased buy box placement. Sellers not using WFS must meet strict fulfillment and delivery standards, including two-day shipping eligibility, to remain competitive. Walmart prioritizes customer experience, so order tracking, fast delivery, and low return rates are critical to success on this platform.

4.- Etsy

Etsy is a niche marketplace focused on handmade, vintage, and unique items. Most Etsy sellers manage fulfillment independently, as the platform does not offer a centralized fulfillment solution. This gives sellers complete control over their packaging, branding, and shipping timelines.

5.- Shopify and DTC (Direct-to-Consumer) Fulfillment

Shopify powers independent online stores and gives sellers full control over their fulfillment strategy. Sellers can use Shopify’s built-in shipping tools, integrate with third-party logistics (3PL) providers, or fulfill orders in-house.

For those looking to scale, Shopify Fulfillment Network (SFN) is an option that provides similar benefits to FBA, such as distributed inventory and two-day delivery. Managing fulfillment through Shopify requires more setup and responsibility, but it also allows for complete brand control, making it ideal for direct-to-consumer (DTC) brands that value autonomy and customer relationships.

Managing fulfillment across multiple marketplaces

As you saw, each marketplace has its shipping standards, inventory policies, and customer expectations, which can quickly lead to operational headaches without the right systems in place. Coordinating orders, tracking stock levels, and ensuring timely delivery across platforms requires a well-organized and often automated approach.

Centralized inventory management is key to avoiding overselling or stockouts. Sellers often rely on multichannel software to synchronize product availability in real-time across all platforms. Similarly, order management tools help consolidate shipments and streamline label printing, warehouse coordination, and tracking updates.

It’s also essential to understand and comply with each marketplace’s service-level agreements (SLAs), especially regarding shipping times, return handling, and customer service responsiveness. 

By investing in integrated tools and refining logistics processes, sellers can create a seamless, scalable fulfillment operation that supports consistent customer satisfaction, regardless of where the sale originated. 

Now that you’ve learned more about fulfillment within marketplaces, don’t forget to share this article on social media and stay tuned to our blog for more updates.