Nexus Logic SystemsShopify apps

How to add stock to Shopify from a supplier invoice and record what it cost

Updated · By Senoussi, developer of True COGS at Nexus Logic Systems

Short answer

Shopify receives stock against a purchase order or a transfer, or when you change quantities by hand; it has no step that reads a supplier's invoice. The cleanest route is to enter the invoice as a purchase order in Shopify, with each line's unit price, and receive it: True COGS then records each price into your weighted average (or FIFO) and Cost per item, so nothing is typed twice. Apps such as Smart Restock and Invoice Importer read the invoice file itself.

Doing it by hand in Shopify

Shopify's receiving is built around purchase orders and inventory transfers (Shopify Help). When the paperwork you get is the supplier's invoice, the usual routine is:

  1. Open each product on the invoice in Shopify admin.
  2. Add the quantity received to the right location.
  3. Work out the new cost for the variant, ideally the weighted average, not just the invoice price, and type it into Cost per item.
  4. Repeat for every line, then check that what you entered adds up to the invoice total.

For an invoice of 50 lines that is 100 separate entries, and Cost per item keeps no record of which invoice set it.

Where typing goes wrong

  • The wrong product. Two sizes or colours with near-identical names on the invoice.
  • A price typed as the cost of the whole line, or the line total typed as the unit price.
  • The newest price overwriting the average, so every unit already on the shelf is re-costed at the new price (see the worked example).
  • Freight and duty left out, so the cost is too low. See landed cost per unit.

Recording the cost with True COGS

  1. Create a purchase order in Shopify from the invoice: each product, its quantity, and its unit price before tax.
  2. Create the transfer from it and receive the stock as usual. True COGS records each line's price for the units received, blends it into your weighted average (or FIFO on paid plans) and writes the result to Cost per item.
  3. Stock already added by changing quantities? The day after, those lines are on True COGS's Waiting page with prices filled in: check each against the invoice and save.
  4. Freight and duty on the invoice go on the Landed cost page (paid plans), shared into each unit's cost. See landed cost per unit.

True COGS does not read the invoice file itself. It is free for up to 25 variants with a cost on record; the App Store listing has current prices.

If you use an app that reads the invoice

An invoice reader that shows only its successes is guessing politely. Before you trust one with your costs, check that it:

  • Asks when a line could be two of your products, instead of choosing one.
  • Checks the arithmetic: each line's quantity × unit price against its line total, and the lines against the invoice total.
  • Lists what it could not read, such as a credit or a weight, rather than dropping it.

Also check what it writes to Cost per item. Smart Restock, for example, says that with it your cost per item reflects what you last paid (its App Store listing). An average blends each delivery into the stock you already hold instead; see FIFO vs weighted average.

Questions merchants ask

Can Shopify import a supplier invoice?

Shopify receives stock against purchase orders and transfers, or by changing quantities by hand. To turn a supplier's invoice file into stock and cost, you type it in or use an app that reads invoices.

Which app adds stock to Shopify from a PDF invoice?

Smart Restock and Invoice Importer read supplier invoices; check how each sets Cost per item. True COGS does not read the invoice: it records the price when you receive the stock on a purchase order, or confirm it on its Waiting page.

Does reading an invoice update Cost per item?

It depends on the app, so check its listing. With True COGS, the price on the purchase order you receive goes into your weighted average (or FIFO) and Cost per item is updated.

Is True COGS free?

It is free for up to 25 variants with a cost on record. Paid plans start at $29 a month or $290 a year.

Try True COGS free. True COGS is an inventory costing app for Shopify by Nexus Logic Systems. It records the price you paid on every delivery (a received purchase order or a transfer), with its share of freight and duty on paid plans, keeps every price with its date, and writes your moving weighted average cost, or FIFO cost on a paid plan, to Shopify's Cost per item. It is free for up to 25 variants with a cost on record; paid plans start at $29 a month or $290 a year.

Install from the App Store

Sources