Plenty of stores buy the same product from two or three distributors - whoever has it in stock this week, whoever gets you to free shipping, and then price. Stockroom lets you record all of them against an item, each with their own part number, case size and minimum, and shows you what each one last charged you.
Add a supplier to an item
Open a product and find the Supplier ordering section. Under Other suppliers for this item, click Add a supplier, pick one from your supplier list, and fill in whatever applies:
Supplier SKU - their part number for this item. It prints on the purchase order you send them, and it is what their order sheet matches on when you import one. Leave it empty and their purchase orders use the item's Default supplier SKU. You can also set it straight from a purchase order line - see Editing a supplier SKU while you order below.
Pack size and Pack name - how many units they ship together, and what they call it. The "3 cases of 4" breakdown on a purchase order comes from here.
Minimum order - the fewest units they will sell you of this item.
Every field is optional. Naming a supplier and leaving the rest blank is still worth doing - it records that they carry the item, which is what the rest of this article builds on.
The values at the top of the Supplier ordering section, including the Default supplier SKU, are your fallback, used for any supplier without a value of their own. A supplier's row wins field by field - so a distributor who only sells the case can sit at a pack size of 12 while the item itself stays at 1.
Already keep supplier part numbers on a Shopify metafield? Link it once under Settings > Data & sync > Linked metafields and Stockroom fills the Default supplier SKU from your catalog, on products, purchase orders, PDFs and labels, and keeps it in sync as the catalog changes. A variant's own metafield value wins over its product's. While linked, editing the default in Stockroom saves back to the metafield, and per-supplier SKUs still win on that supplier's orders. Removing the link leaves every supplier SKU in Stockroom as it was. Pack size and minimum order quantity can be linked to whole-number metafields in the same card.
What each one last charged
Beside each supplier you will see Last paid $4.50 on 3 Aug, or Not ordered from yet. That comes from your own purchase orders - the most recent one you actually placed with that supplier for that item, after any line discount. Drafts do not count, and freight is not baked in.
It sits beside the supplier's price list, and the two never overwrite each other - one is what you actually paid, the other is what the supplier says it costs today.
Keep a supplier's price list
Each supplier can also carry a price list of what they charge you, in their own currency, on the Price list tab of the supplier's page. Your purchase orders start from it. Removing items, filling prices from Shopify cost, quantity breaks and importing the supplier's own file are covered in Keep a supplier's price list.
Editing a supplier SKU while you order
You do not have to come back to the product page to fix a part number. On a purchase order, click the note icon at the end of any line and you get a Supplier SKU field, already filled in with whatever is on record for that supplier.
Change it and two things happen: this order prints the code you typed, and the item's record for that supplier is updated so your next order fills it in. The field also works on an order you have already sent - a part number is not a change to what you ordered.
Clearing the field only affects that order. Your saved part number for the supplier stays as it was - the product page is where you remove one.
While you build a purchase order
Add an item to a purchase order and, if another supplier on record last charged less for it in the same currency, the line says so quietly: Distributor B charged $4.20. It is a note, not a warning - nothing moves the line, and nothing tells you to switch.
Everything else follows the supplier the order is for: their part number prints on the PDF, their pack size drives the pack breakdown, and importing their order sheet resolves part numbers against them first - the same code on a different supplier's file is not treated as a match. See Creating a purchase order from a CSV file.
When you would rather have the choice made on price, Reorder can group its suggestions by the lowest-cost supplier - see Reorder from the lowest-cost supplier.
Set them in bulk by CSV
For more than a handful of items, use Export CSV and Import CSV on the Inventory page. A supplier column takes a comma-separated list, and supplier_sku, pack_size, pack_unit, min_order_qty and supplier_price line up with it by position: Distributor A,Distributor B against DA-1001,DB-88 gives each of them their own code. The full rules for lining columns up are in Import and export reorder points by CSV.
supplier_price sets that supplier's list price, with dot decimals (3.85, never 3,85). A cell holding clear removes the price. The item stays on the supplier's list.
The primary_supplier column shows and sets each item's primary supplier by name. Naming one links them to the item if needed, and clear removes the pin.
Download a template in the import dialog gives you the columns with an example row already in place.
Good to know
Removing a supplier from an item also takes the item off that supplier's price list, with its price, supplier SKU, pack size and minimum order for them. You can restore it from the price list. Purchase orders you already sent them, and the costs on them, are untouched.
Costs are shown in the currency you paid in. Stockroom never converts one supplier's price into another's currency to compare them - a converted figure is one nobody quoted.
Reorder suggestions use the item's own pack size and minimum, not a particular supplier's, because the suggestion is worked out before you have picked one. The per-supplier values take over on the purchase order itself.
Which supplier a product is grouped under on the Reorder page still comes from your auto-assign rules - the extra suppliers here are alternatives you can see, not a second reorder list. See Suppliers: automatic imports, details, and product rules.
Free freight is set per supplier rather than per item: fill in Free freight over on the supplier and every purchase order for them shows how close the subtotal is.