Amazon FBM vs FBA: Which Is Better for Shipping?
Amazon sellers face a fundamental shipping decision: fulfill yourself (FBM — Fulfilled By Merchant) or let Amazon handle it (FBA — Fulfilled by Amazon). Both have trade-offs. Your product, volume, margin, and operational capability determine the right answer.
FBA: Fulfilled by Amazon
You send inventory to Amazon's warehouses. Amazon picks, packs, ships, and handles returns. You pay storage + fulfillment fees ($2-5+ per unit depending on size). Your product becomes Prime-eligible — which usually doubles or triples conversion.
FBM: Fulfilled by Merchant
You store, pick, pack, ship, and handle returns yourself. No Amazon fulfillment fees but no Prime badge (unless you enroll in Seller Fulfilled Prime). Lower unit economics for small items; better for large, low-turnover, or hazmat items that Amazon won't store.
Shipping Cost Comparison
- FBA: $2-5 per unit in pick-pack fees + $0.50-1.50 in monthly storage fees + Amazon-negotiated shipping rates
- FBM: Your carrier rates (USPS/UPS/FedEx) typically $4-10 per package + your in-house labor
- Break-even: Usually around $30+ unit sale price for profitable FBM. Under that, FBA margins are better
When FBA Makes Sense
- Small, lightweight items (FBA fees scale with size — FBA is cheaper for small items)
- High-turnover items (storage fees eat margin on slow-sellers)
- Products benefiting from Prime badge (most consumer categories)
- You don't want to manage warehousing or customer service
- Multi-channel: FBA can ship to non-Amazon customers (Multi-Channel Fulfillment)
When FBM Makes Sense
- Large or heavy items (FBA oversize fees are punishing)
- High-margin products where $2-5 in FBA fees is significant
- Hazmat, regulated, or custom-made products FBA won't handle
- Slow-selling inventory (FBA long-term storage fees after 180 days)
- You already have efficient fulfillment operations
Seller Fulfilled Prime (SFP)
Amazon's middle path — you fulfill but get the Prime badge. Requires meeting strict performance standards: 2-day delivery to most US addresses, weekend delivery capability, under 1% late shipment rate. Hard to qualify for but valuable when you do.
The Decision Framework
- Calculate your all-in cost per unit for FBA (product cost + shipping to Amazon + FBA fees + storage)
- Calculate your FBM cost (product cost + outbound shipping + labor per order + returns cost)
- Add the Prime conversion lift (FBA products typically sell 20-40% better than non-Prime)
- Whichever has higher net margin wins
Hybrid Approach
Many sellers use both. Small, bestselling SKUs go FBA for Prime. Large, slow, or special items go FBM. This maximizes margin while getting Prime benefits where they matter most.