← Amazon FBA vs FBM calculator
Sellers search this after Amazon invites the account to Seller Fulfilled Prime. FBA already has the Prime badge. SFP keeps that badge if you buy a 2-day label and pack on time. Merchant fulfilled is the cheaper Ground label without Prime. The main calculator’s FBA vs FBM table does not model that badge, so a completed-sale leftover can hide a take-rate gap.
On the default $29.99 large-standard unit, FBA keeps $4.03 more per session than SFP ($7.70 vs $3.67), $460.37 on 80 FBA units. Amazon’s $4.15 pick plus inbound is cheaper than an $8.95 2-day label and 6 minutes at $18. The 2-day label has to fall to about $2.75 before SFP matches. A $2.40 label flips SFP ahead by $0.23 per session, $26.20 a month. Merchant fulfilled keeps $11.64 on a completed sale but only $4.66 expected at 40% take — it needs about 66.1% to match FBA.
| Path | Take | Ship / pick | Completed | Expected | vs FBA |
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Expected leftover is take × completed sale on the same visitor pool (typed FBA units ÷ FBA take). Return mix is held at zero so this table stays a badge-and-label question. Complementary to FBA vs FBM on the main calculator (no Prime take), to MCF for website orders (a non-Amazon checkout from FBA stock), and to expected returns. Paste the 2-day label from Buy Shipping and the take rates from your conversion report. This page does not publish Amazon’s live SFP SLA or fee schedule.
The calculator is arithmetic, not advice. It does not recommend leaving FBA, joining Seller Fulfilled Prime, or dropping the Prime badge.
On the calculator defaults — a $29.99 large-standard unit, 15% referral, $4.15 FBA pick, $8 cost of goods, a $8.95 2-day label, and 6 minutes at $18 — FBA keeps $4.03 more per session than Seller Fulfilled Prime ($7.70 vs $3.67), $460.37 on 80 FBA units. The 2-day label has to fall to about $2.75 before SFP matches. Merchant fulfilled without Prime keeps $4.66 because the Ground label is cheaper, but 40% take is not enough; it needs about 66.1% to match FBA.
No. Seller Fulfilled Prime keeps the Prime badge, so take is usually close to FBA, but you buy a 2-day label and pack the order. Merchant fulfilled drops the Prime filter and usually converts fewer sessions. The page shows all three on the same visitor pool. It does not recommend a fulfillment method and it does not publish Amazon's live SFP SLA.
When the 2-day label plus pack time is cheaper than Amazon's pick fee, inbound, and storage after the take-rate gap. On these defaults a $2.40 2-day label flips SFP ahead by $0.23 per session, $26.20 on 80 FBA units. A bulky pick fee can also flip the table. Replace the label and take rates from your own Buy Shipping preview and conversion report.