Marketplace fulfilment or self ship: how to decide
Compare marketplace fulfilment against self shipping on fully loaded cost per order and learn which stock should never go into a platform warehouse.
A decision most sellers make by default
Every marketplace seller picks one of three arrangements. The platform stores and ships your stock from its own warehouse. The platform's courier collects from your premises on its schedule. Or you pack and ship with your own courier account. Most sellers end up where they started rather than where the arithmetic points.
The comparison is worth doing properly because it is not one decision. It is a decision per SKU. The arithmetic that favours a platform warehouse for your fastest mover usually argues against it for the slow half of your catalogue.
The fee stacks and what neither removes
Neither arrangement removes your responsibility for stock-outs, listing quality or the decision about what to do with returned units. Platform fulfilment moves the labour and not the accountability. Fee schedules are also revised periodically so any model you build needs rechecking rather than trusting.
Platform fulfilment charges inbound freight to the fulfilment centre, a fulfilment fee banded by weight and size, monthly storage by volume, a surcharge on stock that sits too long and a fee to remove or dispose of what you want back. Labelling and prep requirements add handling before the stock even ships.
Self shipping looks cheaper per parcel and carries costs that do not appear on a courier invoice. Packaging, the person who packs, the floor space, the failed pickup that costs you a day on the delivery promise and the time spent handling reverse logistics yourself. Your courier rate also depends on volume so the quote a larger seller mentions is not the quote you will get.
The stock that should stay out of a platform warehouse
Do not send your whole catalogue into marketplace fulfilment. It is the most common and most expensive version of this decision. Slow-moving SKUs accumulate monthly storage and then a long-term surcharge and you end up paying rent on stock that was already a mistake. Sending the long tail converts a slow-stock problem into a recurring bill with a removal fee attached at the end.
Bulky low-value items have the same problem in volume terms. Products with batch or expiry constraints add a third risk because stock you cannot inspect or rotate can age out of saleability in someone else's warehouse. A seller who cannot forecast replenishment should stay out until they can because an empty bin in a platform warehouse costs ranking rather than just a sale.
There is an opposite case. If you cannot reliably meet pickup cut-offs or your on-time delivery metrics are already slipping then self shipping is the riskier choice. Marketplace account health responds to late dispatch and a suspended account earns nothing while you argue about courier reliability.
Working it out per SKU
Sort the catalogue by units sold rather than by revenue. Take the top band and model the fully loaded cost per delivered order both ways. For platform fulfilment that is inbound freight plus the fulfilment fee plus storage multiplied by the days you expect to hold it. For self shipping it is courier rate plus packaging plus a realistic allocation of labour and space.
Then account for the part that is not a cost. Platform fulfilment generally produces a faster and more certain delivery promise and the promise on the listing influences whether shoppers buy. Treat that as a reason the options are not comparable on cost alone rather than as an uplift you can budget.
The answer for most sellers is a split. Fast movers in the platform warehouse where storage days are few and the delivery promise does the most work. Long tail and bulky items self shipped. Review the split each quarter because velocity changes and a SKU that earned its place in the fulfilment centre last season may not deserve it now.
The numbers to compare
The metric that matters is fully loaded cost per delivered order by SKU alongside your on-time dispatch and delivery performance. Both halves are needed. A cheaper arrangement that damages account health is not cheaper.
The metric that flatters is the headline courier rate per shipment. It is the number sellers quote to each other and it excludes packaging, labour, failed pickups, storage and the handling of returns. The blanket claim that platform fulfilment is expensive usually rests on that comparison and it falls apart the moment labour is priced.
The mistake in the comparison itself
The common mistake is setting the courier rate against the fulfilment fee and deciding there. The two numbers are not equivalent. The fulfilment fee includes picking, packing, shipping and the first line of return handling. The courier rate includes transport only.
It is expensive because the omitted items are the ones that scale with your orders. Packing labour, packaging and the hours on reverse logistics all grow as you grow while the courier rate per parcel looks flat on the invoice. Sellers who run this comparison once at low volume carry the wrong answer for years.
Plan the peak before the peak
Inbound appointments and receiving times at platform warehouses stretch as a festive season approaches and stock in transit is stock you cannot sell. If you intend to use platform fulfilment for a peak then the decision and the inbound shipment belong weeks earlier than feels necessary. Check the current fee schedule and labelling requirements at the same time.
This guide explains how something works. It is not legal, tax or financial advice, and rules change. Confirm anything regulatory with a qualified professional before you act on it.