Comparing the Best Amazon 3PLs for Sellers

Amazon sellers have more fulfillment options than ever, but choosing the right setup gets more complex as you grow. What works early with FBA often starts to break down as order volume increases, inventory spreads across channels and costs become harder to control.

That’s where an Amazon 3PL becomes part of the conversation. A 3PL provider can support FBA prep, direct fulfillment and broader supply chain operations, giving your ecommerce business more flexibility across channels and more control over how orders are handled.

This guide breaks down how Amazon fulfillment models compare and what to look for when evaluating 3PL companies. Whether you’re expanding beyond FBA or looking to improve performance across your supply chain, the goal is to help you choose a setup that supports how your business operates today and where it’s headed.

Key Takeaways

• An Amazon 3PL helps you manage FBA prep, FBM fulfillment and multi-channel operations without relying entirely on Amazon’s network
• The right 3PL provider depends on your fulfillment mix, ecommerce business model and long-term supply chain needs
• FBA works well for speed and Prime eligibility, but introduces cost, storage and flexibility constraints
• Many 3PL companies support basic fulfillment, but fewer can connect Amazon workflows with broader ecommerce platforms
• Cart.com stands out for brands that need Amazon support, omnichannel fulfillment and operational visibility that protects customer satisfaction
  

Table of Contents

• What is an Amazon 3PL?
• What is Amazon FBA?
• What is FBM?
• What is seller-fulfilled Prime?
• When Amazon sellers need a 3PL
• How to evaluate an Amazon 3PL: 5 factors to consider
• The best Amazon 3PLs: a comparison
• Cart.com
• Amazon FBA
• Amazon multi-channel fulfillment (MCF)
• ShipBob
• Red Stag Fulfillment
• eFulfillment Service
• ShipMonk
• FAQs
• Partner with Cart.com

What is an Amazon 3PL?

An Amazon 3PL is a third-party logistics provider that handles storage, FBA prep and order fulfillment for sellers operating on Amazon.

Instead of relying entirely on the Amazon fulfillment network, sellers use a 3PL provider to:

• Prepare inventory for FBA through labeling, bundling and compliance support
• Fulfill orders directly through FBM or Seller-Fulfilled Prime
• Manage inventory across Amazon, ecommerce platforms and other channels
• Improve supply chain flexibility as order volume and channel complexity grow

For an ecommerce business, the goal is simple: reduce dependency on Amazon fulfillment services and its infrastructure while maintaining speed, control and cost efficiency. The right setup can also protect customer satisfaction by keeping orders accurate, inventory visible and fulfillment consistent.

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What is Amazon FBA?

Amazon FBA (Fulfillment by Amazon) allows sellers to send inventory to Amazon’s warehouses. Amazon handles storage, picking, packing, shipping and customer service.

FBA simplifies operations and unlocks Prime eligibility, but it comes with tradeoffs that become more noticeable over time:

• Storage fees increase over time, especially for slow-moving Amazon inventory

• Inventory limits can restrict how much you can send into Amazon

• Returns, packaging and customer experience are controlled by Amazon

For many sellers, these constraints start to impact margins and flexibility as they scale. That’s often the point where a 3PL becomes part of the fulfillment strategy, either to supplement FBA or reduce reliance on it.

What is FBM?

Fulfilled by Merchant (FBM) means you store and ship orders yourself or through a 3PL.

Instead of routing orders through Amazon’s network, a 3PL fulfills them directly from its own warehouses. This advantage of a 3PL gives sellers more control over how inventory is stored, shipped and presented to customers.

This approach is often used when sellers want to:

• Reduce FBA storage costs
• Maintain control over packaging and branding
• Improve margins on certain SKUs
• Fulfill orders across multiple channels from the same inventory pool

FBM introduces more operational responsibility, but a 3PL can take on that complexity while keeping fulfillment consistent.

What is Seller-Fulfilled Prime?

Seller-Fulfilled Prime (SFP) allows sellers to offer Prime shipping while fulfilling orders outside of Amazon’s warehouses.

To qualify, sellers need to meet strict performance requirements:

• Fast, consistent delivery speeds
• Reliable warehouse operations
• Strong SLA compliance and on-time and expedited shipping

Maintaining those standards manually can be difficult, especially during peak periods. Many sellers rely on a 3PL to meet SFP requirements at scale while maintaining control over inventory and fulfillment.

When Amazon sellers need a 3PL

Not every seller needs a 3PL immediately. But certain inflection points make a 3PL provider necessary.

You’re likely ready for an Amazon 3PL if:

• FBA storage fees are increasing and cutting into margins
• You’re hitting inventory limits or dealing with stockouts
• You’re expanding beyond Amazon into D2C, retail or wholesale
• You need more control over packaging, returns or customer support
• You want to reduce supply chain risk tied to a single fulfillment channel
• Your ecommerce business needs one inventory strategy across multiple ecommerce platforms

Many brands start with FBA, then layer in a 3PL provider to regain control over costs, inventory and operations as complexity increases. Over time, fulfillment shifts from a single-channel setup to a more flexible model that supports multiple channels and fulfillment paths.

How to evaluate an Amazon 3PL: 5 factors to consider

Finding the right Amazon 3PL requires evaluating how well a 3PL provider supports FBA prep, FBM fulfillment and your broader selling strategy.

The focus should be on how each provider fits your Amazon requirements, ecommerce platforms and supply chain goals. As order volume and SKU counts increase, gaps in visibility, warehouse management, inventory coordination and fulfillment speed become harder to manage.

Distribution locations

Does the 3PL provider have fulfillment centers near your customers and Amazon receiving hubs?

Warehouse locations affect shipping speed, inbound FBA costs and delivery times. For sellers comparing 3PL companies, network coverage can make a meaningful difference in both cost and customer satisfaction.

Scalability

Can the 3PL provider handle peak season challenges, Prime events and seasonal demand spikes?

Amazon sellers need consistent performance during high-volume periods. A strong 3PL provider should have the staffing, warehouse management processes and operational controls to support growth without disrupting customer experience.

Fulfillment accuracy

Does the 3PL provider maintain high pick, pack and ship accuracy rates?

Errors lead to negative reviews, returns and account health risks. The best 3PL companies use warehouse management standards and quality checks to reduce mis-picks, delayed shipments and inventory discrepancies.

Integration

Does the 3PL provider integrate with Amazon Seller Central, FBA workflows, MCF, inventory management systems and other ecommerce platforms?

Seamless data flow is critical for inventory visibility, order routing and data-driven decisions. Without strong integrations, teams often rely on manual updates that slow down fulfillment and increase risk.

Fees

Are pricing and storage costs transparent and predictable?

Hidden fees can quickly erode margins, especially for FBA prep, returns and multi-channel fulfillment. When comparing companies, look at how each 3PL provider prices storage, pick and pack, inbound receiving and special projects. Also determine if they offer predictive analytics with the support of real-time insights to determine fees.

The best 3PL for Amazon sellers: a comparison

Amazon sellers have several fulfillment options, each designed for different stages of growth and operational complexity. The right choice depends on how you balance FBA, FBM, multi-channel fulfillment and how much control your ecommerce business needs over inventory, costs and operations.

Some 3PL companies are built to support Amazon-first models, while others are designed to manage fulfillment across multiple ecommerce platforms. Understanding those differences helps you choose a 3PL provider that fits both your current setup and how your business is likely to evolve.

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Cart.com

Cart.com provides a unified approach to Amazon fulfillment, combining FBA prep, FBM support and multi-channel logistics in one system.

Inventory can be received, prepared and routed to Amazon fulfillment centers while also supporting direct fulfillment from the same network. This allows brands to manage FBA and non-FBA operations without splitting inventory or relying on separate providers.

This includes handling inbound inventory, preparing products to meet Amazon requirements and routing inventory across fulfillment nodes based on demand. As order volume increases, that coordination becomes critical to maintaining speed, cost control and supply chain flexibility.

Instead of operating as a standalone warehouse provider, Cart.com connects fulfillment operations with inventory management, marketplace execution and customer engagement. That alignment becomes more important as order volume, SKU count, ecommerce platforms and channel complexity increase.

Best for

Brands managing both Amazon and non-Amazon channels, especially those dealing with high SKU counts, multiple fulfillment models or rapid growth. This includes sellers running both D2C and Amazon operations, as well as brands expanding into retail or wholesale.

Cart.com is also a strong fit for an ecommerce business that needs one 3PL provider to support FBA prep, direct fulfillment, warehouse management and operational visibility across channels.

Compared to Amazon FBA and MCF

Amazon’s fulfillment services are optimized for Amazon. Cart.com is built for broader operations that extend beyond a single channel.

With Cart.com, you can:

• Prep inventory for FBA while maintaining control over upstream operations
• Fulfill FBM and SFP orders from the same inventory pool
• Support ecommerce fulfillment, retail replenishment and marketplace orders simultaneously
• Maintain visibility across inventory, costs, warehouse management and performance

This approach reduces dependency on Amazon while improving how inventory and orders are managed across channels.

Amazon FBA

Amazon FBA is the default fulfillment model for many Amazon sellers. It allows you to store inventory in Amazon’s warehouses while Amazon handles picking, packing, shipping and customer support. This makes it easy to get started, qualify for the Prime badge and reach Amazon Prime Members without building your own logistics infrastructure.

For many sellers, FBA becomes the operational backbone early on, especially when speed and Prime eligibility are critical to conversion. It is also commonly used by brands selling through Amazon Vendor Central, where fulfillment expectations and service levels are tightly controlled by Amazon.

Best for

High-volume Amazon-first sellers that prioritize speed, Prime eligibility and simplified operations. This is often the right fit for brands that primarily sell on Amazon and want to minimize hands-on fulfillment management while maintaining access to Amazon Prime Members.

Compared to Cart.com

FBA reduces the burden of fulfillment, but it comes with structural limitations that become more visible as you scale.

With FBA, sellers often face:

• Rising storage and long-term inventory costs that impact margins
• Inventory limits that restrict how much product can be sent into Amazon
• Limited visibility into warehouse operations and performance
• No support for non-Amazon channels from the same inventory pool

Cart.com gives sellers more control across the entire fulfillment process. You can prep inventory for FBA, fulfill FBM and Seller-Fulfilled Prime orders and support ecommerce fulfillment and retail channels from the same network. That flexibility allows you to improve inventory utilization, better manage inventory costs and adapt your fulfillment strategy as your business grows.

Amazon multi-channel fulfillment (MCF)

Amazon multi-channel fulfillment (MCF) extends FBA by allowing sellers to use Amazon-held inventory to fulfill orders from other sales channels like Shopify, Walmart or direct ecommerce sites. It offers a way to centralize inventory while expanding beyond Amazon.

This approach is often used as a transitional step when sellers begin adding new channels but want to avoid managing multiple fulfillment partners. It can also help maintain faster delivery times for customers by leveraging Amazon’s existing infrastructure.

Best for

Sellers already using FBA who want a simple way to fulfill non-Amazon orders without introducing additional infrastructure. It works best for brands with relatively straightforward operations and limited need for customization.

Compared to Cart.com

MCF adds convenience, but it still operates within Amazon’s constraints.

Sellers using MCF often encounter:

• Amazon-branded packaging that limits control over the customer experience
• Pricing that is typically higher than independent 3PL alternatives, increasing overall inventory costs and fulfillment expenses
• Limited customization for packaging, workflows and returns
• Less flexibility in handling complex or high-SKU operations

Cart.com provides multi-channel fulfillment without these restrictions. Orders across Amazon, ecommerce and retail channels can be fulfilled from a shared inventory pool, with consistent packaging, workflows and visibility. This makes it easier to scale across channels while maintaining control over both cost and customer experience.

ShipBob

ShipBob is a widely used 3PL focused on ecommerce fulfillment, with a strong presence among direct-to-consumer brands. It offers a distributed fulfillment network and a platform designed to simplify order management and shipping for growing businesses.

Its model is built around standardization and ease of onboarding, which makes it accessible for brands transitioning away from in-house fulfillment.

Best for

Mid-market ecommerce brands with predictable order volume and relatively straightforward fulfillment needs. ShipBob is often a fit for businesses that want to outsource fulfillment quickly without building complex workflows or managing multiple systems.

Compared to Cart.com

ShipBob is designed for ease of use, but that simplicity can create constraints as operations become more complex.

Common limitations include:

• Less flexibility for high SKU counts or complex inventory management
• Limited support for blended fulfillment models like FBA prep and FBM at scale
• Standardized workflows that may not align with unique operational requirements
• Less depth in supporting enterprise-level or multi-channel operations

Cart.com is built for brands operating across multiple channels and fulfillment models. Instead of fitting into a fixed system, Cart.com supports more complex workflows, higher SKU counts and integrated Amazon and non-Amazon operations.

For an ecommerce business comparing 3PL companies, the key difference is operational depth. Cart.com connects fulfillment, marketplace management and inventory visibility so teams can manage growth across ecommerce platforms with fewer handoffs.

Red Stag Fulfillment

Red Stag Fulfillment is a specialized 3PL focused on heavy, oversized or high-value products. Its operations are designed around accuracy, damage prevention and handling complex physical goods that require more care during fulfillment.

This specialization makes it a strong option for brands where shipping errors or product damage carry a higher cost.

Best for

Brands shipping large, bulky, or fragile items where precision and product handling are critical. It’s particularly well-suited for companies with a narrow product range that requires specialized fulfillment processes.

Compared to Cart.com

Red Stag’s specialization delivers strong performance for a narrow set of use cases, but limits its applicability for broader ecommerce operations.

Considerations include:

• A more limited fulfillment network compared to larger providers
• Less support for multi-channel strategies involving retail, marketplaces and D2C
• Narrower focus that may not align with standard ecommerce product categories
• Reduced flexibility for brands with diverse product assortments

Cart.com supports a wider range of product types and fulfillment scenarios. From standard ecommerce SKUs to more complex operations, it provides the infrastructure needed to manage inventory and fulfillment across multiple channels.

eFulfillment Service

eFulfillment Service is a long-standing 3PL that focuses on affordability and accessibility. It offers straightforward fulfillment services with minimal onboarding requirements, making it easier for smaller sellers to get started.

Its model is designed to remove barriers to entry rather than support highly complex operations.

Best for

Early-stage or low-volume sellers looking to outsource fulfillment without committing to advanced systems or higher-cost providers. It’s often used by businesses testing demand or operating with a limited SKU catalog.

Compared to Cart.com

Lower cost can be appealing, but it often comes with tradeoffs that limit long-term scalability.

These can include:

• Limited infrastructure to support high order volumes or rapid growth
• Fewer integrations with modern ecommerce and marketplace platforms
• Less visibility into inventory, performance and operational metrics
• Reduced ability to support complex fulfillment models or multi-channel expansion

Cart.com is designed for brands planning to grow. It supports higher volumes, more complex operations and integrated fulfillment across Amazon, ecommerce and retail channels.

For sellers comparing 3PL companies, this matters when a low-cost entry point no longer supports the pace or complexity of the business. As an ecommerce business expands, the right 3PL provider should support stronger warehouse management, better visibility and more flexible supply chain execution.

ShipMonk

ShipMonk is a technology-driven 3PL that provides fulfillment services for ecommerce brands, with a focus on automation, integrations and operational efficiency. Its platform is designed to streamline order processing and provide visibility into fulfillment performance.

It’s often positioned as a step up from entry-level 3PLs, with stronger technology and reporting capabilities.

Best for

Growing ecommerce brands that need more advanced capabilities than entry-level 3PLs, especially those expanding across multiple channels and looking for better system integration.

Compared to Cart.com

ShipMonk offers a strong technology foundation, but may not provide the same level of operational depth and integration across services.

Potential limitations include:

• Fulfillment-first focus without broader integration into marketplace or operational workflows
• Less flexibility in managing highly complex or large-scale fulfillment environments
• Limited ability to unify operations across multiple business functions
• Less hands-on operational support compared to more integrated providers

Cart.com connects fulfillment with the broader commerce ecosystem. Inventory, order management, marketplace operations and customer experience are aligned within a single system, giving brands better visibility and control across the entire lifecycle of an order.

For sellers evaluating 3PL companies, this broader model can be valuable when fulfillment needs to connect with customer support, marketplace execution and multiple ecommerce platforms.

Partner with Cart.com for Amazon 3PL services

Amazon sellers rarely operate in a single channel forever. What starts as FBA often expands into FBM, D2C, retail or wholesale. As that shift happens, fulfillment becomes harder to manage across disconnected systems, inventory pools and partners.

That’s where choosing the right 3PL becomes a critical decision.

Cart.com is built to support that transition without forcing you to rebuild your operations as you grow. Instead of separating Amazon from the rest of your business, fulfillment is managed as part of a broader system that connects warehouse networks, logistics networks and inventory flow.

With Cart.com, you can:

• Prep inventory for FBA and manage inbound logistics with greater control
• Fulfill FBM and Seller-Fulfilled Prime orders alongside FBA from the same network
• Support ecommerce, retail replenishment and marketplace orders without splitting inventory
• Maintain real-time tracking and visibility into inventory, orders, shipping costs and performance

This model helps reduce operational friction while improving how inventory moves across your supply chain. It also gives your team more flexibility to manage delivery times, optimize shipping costs and maintain customer satisfaction as your business grows.

The result is a more flexible fulfillment strategy that adapts as your ecommerce business evolves. You can stay aligned with Amazon’s requirements while reducing dependency on a single channel and improving how inventory and orders are managed across the board.

Talk to a fulfillment expert

FAQs

What is a 3PL for Amazon Sellers?

A 3PL provider for Amazon sellers manages storage, FBA prep and order fulfillment. It helps sellers handle inventory more efficiently while supporting both Amazon and non-Amazon channels. Most 3PL providers also offer broader logistics services such as picking and packing, reverse logistics and coordination across logistics networks to keep orders moving consistently.

Can Cart.com handle my Amazon FBA prep?

Yes. Cart.com manages FBA prep from inbound receiving through labeling, bundling and shipment to Amazon fulfillment centers. This includes coordination with freight forwarding partners and preparation for both domestic and international shipping when needed. These workflows help control shipping costs while maintaining compliance and visibility across the supply chain.

What’s the difference between Amazon FBA and a 3PL?

FBA is Amazon-managed fulfillment. A 3PL provider operates independently, giving you more control over costs, inventory and fulfillment strategy across channels. This includes greater visibility into shipping costs, more flexibility in how orders are fulfilled and access to logistics support that extends beyond Amazon’s network.

Do I need a 3PL if I already use Amazon FBA?

Many sellers use both. A 3PL can reduce FBA costs, handle overflow inventory and support fulfillment outside Amazon. It can also help optimize shipping costs by routing orders through different warehouse networks and fulfillment paths based on demand.

Why is Cart.com the best 3PL for Amazon sellers?

Cart.com supports FBA prep, FBM and multi-channel fulfillment within a single operational model. This allows sellers to manage inventory and orders across Amazon and other channels without splitting systems or workflows, which becomes increasingly important as complexity grows. Its approach to logistics support and integrated warehouse management helps maintain performance across channels.

Why do Amazon sellers move beyond FBA?

As sellers scale, they often need more flexibility, better cost control and the ability to operate across multiple channels. A 3PL provider supports those needs without replacing FBA entirely, helping brands manage shipping costs, expand fulfillment options and improve overall supply chain performance.

How should sellers compare 3PL companies?

Sellers should compare 3PL companies based on Amazon support, fulfillment accuracy, warehouse management, integrations, pricing and scalability. It’s also important to evaluate how each provider supports shipping costs, fulfillment flexibility and long-term supply chain needs. The right choice depends on how your ecommerce business sells today and how your operations will need to adapt as volume grows.