Shopify Supplier CSV Import: A Safe Workflow for 2027

Can you import a supplier CSV into Shopify? The short answer

Yes, for products. Go to Products > Import and upload a CSV in Shopify's product format. But supplier files rarely match that format, and variant metafields are not supported in the product CSV import or export (per Shopify Help, checked November 10, 2026). So a supplier spec sheet with thickness, pack coverage or finish options can't go in through that route.

If your goal is to put supplier specs into variant metafields on products you already sell, that is a different job from creating or overwriting products. Shoperize Variant CSV is built for that job. The table below helps you pick the right path.

Your job	Right path	Why
Create new products from a supplier file	Native product CSV import (or a product import app)	Needs titles, handles, options, images, prices in Shopify's format
Update price and inventory	Native import, bulk editor, or an inventory tool	Variant CSV does not edit prices or inventory
Update variant metafield specs on existing variants	Variant-level import by exact SKU, with review	Native product CSV doesn't carry variant metafields

What Shopify's native product CSV import does (and its limits for supplier files)

Shopify's product CSV import is designed to create products and overwrite existing ones. It is good at that. It was not designed to merge a partial supplier file into a catalog you've already built. Here are the behaviors that matter, based on the Shopify import help page.

Handle matching and blank cells

Rows are matched to existing products by handle. If you tick "Overwrite products with matching handles," the file replaces the data for those products. Blank cells in your file overwrite existing values with nothing.

That is the answer to "why did my supplier CSV overwrite values with blanks?" Supplier files often have gaps: a spec missing for one size, a discontinued column. In a native import, each gap can erase something you had already filled in.

Option columns and variant IDs

If you change Option values in the file, Shopify deletes the existing variant IDs and creates new ones. Anything attached to the old variants (apps, integrations, order history references) no longer points at the new variants. A supplier file that renames "Oak Natural" to "Natural Oak" can trigger this.

Size, cancel, history and sorting

• The file limit is 15 MB.
• An import can't be canceled once it starts.
• There is no import history. You can check the activity log, but it is not an undo.
• Sorting rows in a spreadsheet can break image links, because image rows depend on their position under the product.

So back up before you import. Go to Products > Export, choose all products and the CSV for Excel option, and keep that file. The export is also your best template: it shows exactly which columns Shopify expects. Shopify also publishes a sample CSV and required-column list on its CSV format page, which is also where it states that variant metafields aren't supported.

Before you import: prepare the store and the supplier file

Most failed supplier imports are preparation failures. Spend 30 minutes here.

Create metafield definitions first

Go to Settings > Custom data > Variants and create a definition for each spec you want to store. Choose the type deliberately, because it controls what values are valid:

• number_decimal for thickness (7.5) or pack coverage (20.2)
• boolean for waterproof (true or false)
• list of single-line text for finish options
• single-line text for a plank size like 1220x180
• dimension for a single measurement with a unit, such as a 7.5 mm thickness

A dimension holds one measurement and its unit. A "1220x180" cell is two measurements, so either split it into length and width columns or store it as text.

Export SKUs from your store

Export your catalog and pull the variant SKU column. This is your source of truth for matching. Check that every SKU you plan to match is unique. Two variants sharing one SKU makes an exact match ambiguous, and any sensible tool will refuse to guess.

Clean the supplier file

• Save as UTF-8 CSV with one header row.
• No merged cells, notes rows or subtotal lines.
• Trim spaces around SKUs. A trailing space makes "004170 " a different value from "004170".
• Protect leading zeros. Excel turns 004170 into 4170 when it opens a CSV. Format the SKU column as text before editing, or edit in a plain text editor or Google Sheets with the column set to plain text.
• Watch for supplier SKU vs your SKU. If your store uses your own SKUs, add a column with the store SKU, or change the supplier column to match it, before importing.
• Decide on decimal points. "7,5" is a number in some locales and a text string to a validator expecting 7.5.

Finally, export the values you're about to change so you have a before copy. Then you can compare later.

Worked example: supplier spec file to variant metafields

Say you sell luxury vinyl plank flooring. Your supplier sends a spec file. Here is the raw file, with the six columns as the header row, shown as a table so you can see each cell:

Supplier SKU	Thickness_mm	Pack_Coverage_sqft	Waterproof	Finish_Options	Plank_Size
004170	7.5	20.2	true	Matte|Brushed	1220x180
004180	8	18.7	true	Matte	1220x180
004190	7,5	20.2	false	Brushed|Oiled	1220x180
004200	(blank)	21.5	true	Matte	1520x228
009990	8	19.0	true	Matte	1220x180

In the actual file these are comma-separated lines, and the pipe separates multiple finishes inside one cell. Row 3 has a comma decimal, which in a real CSV must be wrapped in quotes. Row 5 is a SKU the store doesn't carry.

The mapping

Supplier column	Variant metafield	Type
Supplier SKU	(match key, Shopify variant SKU)	Exact match
Thickness_mm	Thickness (mm)	number_decimal
Pack_Coverage_sqft	Pack coverage (sq ft)	number_decimal
Waterproof	Waterproof	boolean
Finish_Options	Finish options	list of single-line text
Plank_Size	Plank size	single-line text

Typed values: where files usually fail

• Boolean: "Yes" and "No" are not true and false. Convert them in the file before import so the value matches the type.
• Decimal: "7,5" should be 7.5. Fix it in the file or expect a validation error.
• Lists: pick one delimiter, then confirm in the review that "Matte|Brushed" appears as two list values, not one string with a pipe in it.
• Dimensions: one measurement plus unit. "1220x180" fails as a dimension, which is why the example maps it to text.

The blank cell rule

Row 4 has no thickness. In a native product import, that blank could wipe a thickness already on the variant. In Variant CSV, a blank cell leaves the existing value unchanged. That makes a partial supplier file safe to run, since gaps don't erase what you already have.

What the review shows

Before anything is written, a before/after review lists each change. For this file it would look like this:

SKU	Field	Before	After	Status
004170	Thickness (mm)	(empty)	7.5	Ready
004170	Finish options	(empty)	Matte, Brushed	Ready
004190	Thickness (mm)	7.5	"7,5"	Error: not a valid decimal
004200	Thickness (mm)	7	7 (blank cell, unchanged)	No change
004200	Pack coverage (sq ft)	20.0	21.5	Ready
009990	All fields	n/a	n/a	Error: SKU not found

You fix the 7,5 row and decide what to do about 009990 (usually: it's a supplier item you don't stock, so remove it). Only then do you approve. For the full walkthrough, see our Shopify variant metafields CSV import step-by-step guide.

One side note for flooring and tile stores: pack coverage is also what drives sell-by-area quantities. If you use Shoperize Price Calculator, package coverage is set in the calculator rules, so decide where your source of truth lives and keep the two consistent.

Step-by-step: run it safely with Shoperize Variant CSV

Shoperize Variant CSV is $14.99/month with a 7-day free trial. Upload, mapping and validation work before purchase, so you can test your supplier file and see the errors before paying.

1. Install and upload. Install from the App Store listing and upload your cleaned UTF-8 CSV.
2. Map columns. Match each supplier column to an existing variant metafield definition, and choose the SKU column as the match key. Save the mapping as a reusable supplier mapping, so next season's file takes minutes.
3. Fix validation and SKU errors. Typed validation flags bad values, and exact unique SKU matching flags SKUs that are missing or duplicated. Correct the file and re-upload.
4. Review before and after. Read the diff. Spot-check three or four variants against the supplier sheet. The change set must be approved before anything is applied.
5. Apply and keep the report. Download the CSV report. If something looks wrong later, history keeps 90 days of changes, and eligible updates can be restored with conflict checks (if a value was edited since the import, it is flagged rather than silently overwritten). Metafields that were newly created by the import can't be automatically undone.

For a before-backup, use the selected-field export to download current values for the metafields you're about to change.

The limits: UTF-8 CSV up to 20 MB, 10,000 rows, 100 columns, and 20 selected metafields per run. Larger supplier files need to be split.

What Variant CSV does not do (pick the right tool)

Variant CSV is narrow on purpose. It does not:

• create products or variants
• edit prices or inventory
• delete anything
• read XLSX files
• fetch supplier files from a URL or FTP
• schedule imports

Here's how to choose.

• New products, titles, descriptions, prices: use Shopify's native product import. Back up first, and mind the blank-overwrite behavior.
• A handful of edits: native metafield editing on the variant page, or the bulk editor, is free and fast enough. See our overview of methods for bulk editing variant metafields for where each one runs out.
• Product creation, Excel files or automation: look at other apps. Matrixify's App Store listing describes bulk import, export and update of store data in Excel and CSV. Csvio's listing describes mapping CSV, Excel and PDF files, with scheduled imports on higher plans. Check each listing for current features and pricing, since they change.

How do I connect a supplier to Shopify?

It depends on how much automation you need. A one-time or seasonal CSV import suits suppliers who send spec sheets a few times a year. A feed-sync app suits suppliers with a regular product feed, where you want scheduled updates. A dropshipping or supplier-connector app suits catalogs where the supplier also handles stock and fulfillment. Variant CSV covers only the first case, for variant metafields.

Keeping supplier specs in sync over time

Treat every supplier update as a small release with the same checklist:

1. Export current values for the fields you'll change.
2. Clean the new file (SKUs trimmed, zeros kept, types converted).
3. Upload, apply your saved mapping, fix validation errors.
4. Review the diff, especially rows where "after" is empty or surprising.
5. Apply, then download and file the report with the supplier name and date.

Agencies running several suppliers benefit most from saved mappings: one per supplier, named clearly, so a new price-list release isn't a new project.

Common errors and fixes

Error	Likely cause	Fix
SKU not found	Leading zeros stripped, trailing space, supplier SKU differs from store SKU	Re-save the SKU column as text, trim, or add a store-SKU column
Duplicate SKU	Two variants share a SKU in the store or the file	Make SKUs unique in Shopify, or remove the duplicate row
Wrong type	"Yes" for a boolean, "7,5" for a decimal, "1220x180" for a dimension	Convert the value in the file, or change the metafield type
Garbled characters	File not UTF-8	Re-export as UTF-8 CSV
Too many rows or columns	Over 10,000 rows or 100 columns	Split the file, keep only the columns you map

If you want a sell-by-area store to run on clean data end to end, start with the supplier specs and then set up calculators on top.

Ready to try it on a real supplier file? Install Shoperize Variant CSV from the Shopify App Store (details at shoperize.com/apps/variant-csv), run your upload and validation on the trial, and find setup help at help.shoperize.com. You can also see all Shoperize apps.

Frequently Asked Questions

Is there a free Shopify supplier CSV import template?

Shopify publishes a sample product CSV on its CSV format help page, and exporting your own products gives you a template that matches your store. The worked example in this article (Supplier SKU, thickness, pack coverage, waterproof, finish options, plank size) is a layout you can adapt for variant metafield specs.

Can I undo a CSV import in Shopify?

Not with the native product import: it can't be canceled and has no import history, so export your products first as a backup. Shoperize Variant CSV keeps 90 days of history and can restore eligible updates with conflict checks, though newly created metafields can't be automatically undone.

Can I schedule supplier CSV imports automatically?

Shoperize Variant CSV does not schedule imports or fetch supplier files remotely, so each run is an upload you review and approve. If you need scheduled imports, check other apps such as Csvio, whose App Store listing mentions scheduled imports on higher plans.

Can Shopify's product CSV import update variant metafields?

No. Shopify Help states that variant metafields aren't supported in the product CSV import or export. You can edit them one by one in the admin, use the bulk editor for smaller jobs, or use an app that imports into variant metafield definitions.

How do I match supplier SKUs to Shopify variants?

Export your catalog, make sure each variant SKU is unique, and clean the supplier file so SKUs are trimmed and leading zeros are preserved. Then match on the exact SKU value. If the supplier uses different SKUs than your store, add a column with your store SKU before importing.