One of the most fundamental decisions for any Amazon seller is about logistics: do you let Amazon handle storage and shipping (FBA, fulfilment by Amazon), or do you ship yourself (FBM, fulfilment by merchant)? Both models have clear strengths and weaknesses, and the right choice depends on your product, your margins and your capacity. This article sets them side by side and gives you a way to decide.

What the two models mean

With FBA you send your goods to Amazon's fulfilment centres. Amazon stores them, packs, ships, and handles customer service and returns. You give up control and pay fees for it.

With FBM you store the goods yourself (or through an external provider) and ship every order on your own. You keep full control and carry the whole operational effort too.

The central differences

  • Cost: FBA bundles many costs into fees (shipping, storage, returns handling) that rise with size and weight. FBM can be cheaper when you have your own shipping rates or storage capacity, particularly with large, heavy or slow-moving products.
  • Prime and the Buy Box: FBA offers are automatically Prime eligible and tend to have better chances at the Buy Box. FBM sellers can only reach Prime through the demanding Seller Fulfilled Prime programme, which sets strict performance requirements.
  • Effort and scaling: FBA scales effortlessly, because Amazon handles the logistics through volume peaks too. FBM ties up more and more of your own resources as volume grows.
  • Control and brand: FBM allows your own packaging, inserts and a branded unboxing experience. With FBA the packaging is standardized.
  • Inventory risk: with FBA you are subject to storage fees, limits and the IPI score. With FBM you steer your own warehouse and carry the full stock risk.

When FBA is the better choice

FBA plays to its strengths on small to medium products that turn over well, where Prime availability decides the purchase. If you want to scale quickly, do not want to run your own warehouse and your margins carry the fees, FBA is usually the pragmatic choice. It is also ideal for sellers who want to concentrate on marketing and range rather than on logistics.

When FBM is the better choice

FBM pays off especially with large, heavy or bulky products where FBA fees eat the margin. It can also make more sense with very slow-moving goods (where FBA storage fees weigh heavily), at low volume, with strongly fluctuating demand, or when you want to offer a distinctive branded unboxing. The requirement is that you can handle shipping and customer service reliably and quickly, because Amazon's performance metrics apply to you too.

Why many people combine both

The decision is not either-or. Many experienced sellers use a hybrid approach: fast-moving small bestsellers through FBA for Prime and the Buy Box, large or slow items through FBM to protect the margin. FBM also serves as a safeguard when FBA storage limits or shortages threaten, so that a product stays available even as the FBA stock runs down.

A way to decide

Ask yourself in order: is Prime decisive for a purchase in my category? How large and heavy is the product? How fast does it turn over? Do I have storage and shipping capacity? How do FBA fees sit against my margin? If Prime matters and the product is small and turns over well, much speaks for FBA. If the product is large, heavy or slow and you can ship efficiently yourself, look seriously at FBM.

In short

FBM and FBA are not a matter of belief but a calculation from product, margin and capacity. FBA buys you convenience, Prime and scalability, against fees. FBM gives you control and can be considerably more profitable on the right products, against effort. For most growing brands the smartest answer is not a strict either-or but a deliberate combination of both models, product by product.