Inventory turns at very different speeds depending on which millimeter of princess cut you bought. A 5mm princess can sit in a tray for a year; a 4mm or 6mm princess can reorder before your supplier finishes invoicing. Wholesale buyers who understand the fast-moving ladder spend less on dead stock and fill more orders. This is the size-by-size reality of princess moissanite, drawn from how the shape actually moves at retail.
The princess cut is a square brilliant with pointed corners, and it is priced partly by that corner exposure. Small princesses, around 2.5mm to 4mm, sell as side stones, eternity band stones and accent pieces. Medium princesses, 5mm to 6.5mm, sell as center stones in solitaire and three-stone rings. Large princesses, 8mm and up, are a niche. The fastest cash usually sits in the middle tier and the small accent tier, not at the extremes.
The fast-moving ladder
The workhorse center size for princess engagement rings is roughly 5mm to 6mm square. That face-up range hits the sweet spot for everyday wear: visible enough to be a center stone, small enough not to overwhelm a working hand. Stock these first, in near-colorless grade, because they reorder constantly. The value-per-carat logic that drives that demand is in princess value per carat.
The second fast tier is the accent range, 2.5mm to 4mm. These feed channel-set bands, three-stone side stones and eternity lines. Because they are bought in matched pairs or rows, they reorder in volume. Production buyers who run channel-set bands and bulk side-stone eternity production are your steady customers for this tier. Keep matched parcels, not loose singles, so reorders match.
The slow movers to watch
Very small princesses under 2mm move only in specialty pave work, and very large princesses above 8mm move slowly because the pointed corners feel intimidating to everyday-wear buyers and the price climbs. Do not open a broad range at the extremes on your first order. Test one small accent size and one large center size, watch the sell-through, and only deepen if the reorder signal is real. The corner-protection concern discussed in our princess corner protection guide is part of why large princesses move cautiously.
Newer buyers often over-order the "interesting" sizes and under-order the boring ones. Resist that. The 5mm near-colorless princess in a plain solitaire is not glamorous, but it is the SKU that pays your rent. The first-order starter pack checklist is built around exactly this logic: anchor on the sizes that move, then experiment.
Set a reorder cadence, not a guess
Once you know which sizes move, replace them on a schedule. A fast-moving 5mm princess should trigger a reorder when stock drops below two weeks of average sales, not when the tray is empty. Smaller accent stones in matched parcels should be reordered by the parcel, so the next batch matches the last. This is the same reorder discipline behind round brilliant size stocking and reorder cadence, applied to a square shape.
Color grading matters for turnover because a warm-toned princess is a harder sale in white gold. Hold D, E or F for center stones; a slightly lower grade is fine in a matched accent row set into yellow gold. Clarity to VS or above is comfortable; inclusions in a square brilliant show less than in an open step cut. Price against the current wholesale price trend so your reorder cost does not quietly outrun your catalog price.
Princess stock wins when it is boring. Pick the fast millimeter ladder, keep matched parcels flowing, and let the slow movers stay small. The turnover numbers will tell you when to expand.
How to read your own turnover data
The fast-moving ladder is a starting point, not a rule. The real answer for your market is in your own sales data. Pull the last twelve months of princess orders and group them by millimeter. You will almost always see a spike at one or two sizes that your customers reorder again and again, and a long tail of sizes that sold once. Double the stock on the spike, cut the tail to a single sample each. Most buyers get this backwards: they keep a broad range "just in case" and tie up cash in sizes that never repeat. Let the numbers tell you the ladder, then buy deep on what moves. The princess sizes that sell in your market may differ from another wholesaler's, and that local signal is worth more than any generic guide.
Above all, resist the urge to fill gaps. A short, well-chosen princess tray that always has the fast sizes beats a wide tray that is missing the one size a customer wants today. Buy deep on what moves, sample the rest, and let turnover guide every reorder. Your goal is never to impress with variety; it is to fill the order in front of you without back-ordering the SKU that pays the bills.