When should I switch from FBA to FBM?
Switch a SKU from FBA to FBM when it costs more in FBA fees than it earns in Prime-badge conversion lift. Common triggers: oversize items where FBA fees exceed 40% of price, slow movers accumulating storage fees, and SKUs with high return rates that never break even after refund reserve.
Jul 26, 2026 · 3 min read
The four SKUs to move to FBM first
Oversize items with FBA fees above 40% of price. Slow movers aged 90+ days paying storage fees. High-return SKUs where refund reserve wipes out margin. Low-price items ($10 or under) where FBA fee is 60%+ of price.
What FBM costs you
You lose the Prime badge on most SKUs (Seller Fulfilled Prime is available but selective), which typically drops conversion by 20% to 40%. You take on shipping, packing, customer service, and returns. Do the math on labour before switching.
Hybrid approach
Keep top movers on FBA for the Prime badge. Move oversize, slow, or high-return SKUs to FBM. Many mature accounts run 70% FBA / 30% FBM by unit count.
Frequently asked questions
Does FBM lose the Buy Box?
FBM competes for the Buy Box, but at a disadvantage against FBA on price parity. Prime-eligible FBM (SFP) closes some of the gap.
Are FBM sellers still eligible for Prime?
Only through Seller Fulfilled Prime, which has strict performance requirements and is not always accepting new sellers.
Does Nova P&L cover FBM SKUs?
Yes. Nova is FBM-inclusive: SKU-level profit calculations work for both fulfilment types.
How fast can I switch a SKU?
Change the fulfilment method in the listing, then submit a removal for FBA units. Full cutover typically takes 2 to 3 weeks.
See this in Nova
Nova surfaces this metric per SKU so you can act before your next monthly close catches it.
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