Keeping best sellers in-house while POD handles the rest

Most sellers who buy a press do not leave print-on-demand. They press the few designs and sizes that sell steadily and let POD carry everything else. Here is what that takes and what it costs.

Why sellers split it

POD is the cheap way to find out what sells. Creators who teach this path say the same thing: test on POD, then bring over only the proven designs.
Stocking blanks works for popular colors and sizes. It does not work for a 3XL in a color you sell twice a year.
POD covers you when you are away, sold out, or buried in December.

How the routing works

On Shopify, sellers describe keeping one listing and two fulfillment locations: their own stock and the POD app. Sizes they hold are assigned to their location and the rest to POD. Shopify routes each line by what is in stock. We did not find the same single-listing setup documented for Etsy.

The cost people miss: orders that ship twice

When one order holds your pressed shirt and an item POD still makes, POD still charges its first-item shipping for its part and you buy a full label for yours. Moving your shirt out of that order saves only POD's additional-item rate, about $2.50 instead of $4.75 in our example. The calculator's “orders that also hold items POD would still ship” field handles this.

POD networks have the same effect inside themselves: two items made by two different providers ship as two packages, each at a first-item rate.

Choosing what to move

Start with the orders that pay best per minute: group orders and anything handed over in person. Why those.
Then steady designs in your two or three best colors, sizes S to XL. Leave the rest of the size run on POD.
Set the share to the hours you have. The calculator shows the hours each share takes and the largest share that fits your month.

Run both for a month before you commit

One printer seller's guide for Etsy shops suggests a 30-day shadow test: keep fulfilling through POD while you record what each order would have cost you in-house. It costs nothing but a spreadsheet, and it replaces every assumption in the calculator with your own numbers.