FBA (Fulfilment by Amazon)

Amazon & D2C glossary · Harpy Media

FBA (Fulfilment by Amazon) is Amazon’s fulfilment service: you send inventory in, Amazon stores it, picks, packs, ships, and handles customer service and returns. Your product becomes Prime-eligible, and Amazon’s network effectively becomes your logistics department — priced per unit, per month, and per behaviour.

What is FBA?

FBA (Fulfilment by Amazon) is Amazon’s fulfilment service: you send inventory in, Amazon stores it, picks, packs, ships, and handles customer service and returns. Your product becomes Prime-eligible, and Amazon’s network effectively becomes your logistics department — priced per unit, per month, and per behaviour.

It’s the single biggest operational decision in most Amazon businesses. FBA buys speed, trust, and Buy Box strength (Prime badge, delivery promises, conversion uplift), and it charges for all of it through a layered fee stack — fulfilment, storage, prep, and long-term penalties. The skill isn’t choosing FBA or not; it’s managing unit economics inside it.

What FBA actually buys you

The list is long and mostly invisible until you lose it: the Prime badge and 1–2 day delivery that shoppers filter and convert on, Buy Box eligibility strength (competing offers are ranked partly on fulfilment), customer service handled by Amazon (messages, returns, refunds), and the operational freedom to scale without hiring a warehouse. Sellers consistently see conversion rate climb when a listing goes FBA — same page, faster promise. Add free returns handling on eligible orders and the CX layer is largely managed for you. That’s the upside the fees are paying for.

What FBA actually costs (the full stack)

The fee schedule reads as one number and behaves as five: fulfilment fee (per-unit pick-pack-ship, by size and weight), monthly storage (per cubic foot, higher in Q4), prep/labelling fees or chargebacks when units arrive non-compliant, aged-inventory surcharges at 180/270/365 days, and removal/disposal fees when stock must leave. The management disciplines that keep the stack lean: accurate dimensions on file (wrong measurements inflate every fee downstream), packaging designed for size tiers, inventory that turns fast enough to never meet an aged-inventory surcharge, and prep done correctly at origin so nothing triggers a manual handling fee. Fees don’t kill FBA sellers; unmanaged fees do.

In practice

A seller moves their top SKU to FBA and watches conversion rise from 9% to 13% on the same traffic — the Prime badge closing shoppers the old listing lost. But the first month’s fee report shows the fulfilment fee running a tier high: the supplier’s new carton added two ounces of packaging weight. A packaging revert later, the unit economics land where the model predicted: faster delivery, better conversion, and a fee line that stopped eating the difference.

How Harpy Media helps

FBA fee architecture — tier engineering, storage discipline, and per-SKU unit economics — sits at the centre of our Amazon operations work.

FBA FAQ

What is FBA?

Fulfilment by Amazon — Amazon stores, picks, packs, ships, and supports your orders for a per-unit fee; your listings gain Prime eligibility.

Is FBA worth it?

For most sellers, almost always — conversion, Buy Box strength, and CX scale beat self-fulfilment. Worth it profitably requires managing the fee stack deliberately.

What are the main FBA fees?

Fulfilment (per unit), monthly storage (per cubic foot), prep/labelling, aged-inventory surcharges, and removal/disposal — plus referral fees on all sales.