What's the difference between 'On hand (current)' and 'On hand (new)' in the Shopify inventory CSV?
Only one of these two columns actually does anything when you upload. Edit the wrong one and your changes will silently vanish — Shopify will look like it accepted the file while your stock counts stay exactly the same.
Why there are two columns at all
When you export inventory from Shopify to edit it offline, the file gives you a before-and-after pair for every SKU/location row: On hand (current) shows what Shopify's records said at export time, and On hand (new) is the blank-for-editing column where you write the count you actually want. That layout exists so you can see the old number right next to the field you're changing, instead of overwriting a number you can no longer see.
Only one of them is read on upload
Shopify reads "On hand (new)" on import and ignores "On hand (current)" entirely — it is display-only, a reference copy of the state at export time, not a live value that gets written back. If you edit "On hand (current)" instead — an easy mistake since it's the first of the two columns and holds a real, currently-accurate number — the upload will still report as successful, because the file is well-formed. It just won't change anything, since the column Shopify actually checks was never touched.
A related trap: sorting or filtering between export and upload
Because the two columns sit side by side per row, sorting or filtering the sheet after export (by SKU, by product name, by location) is usually safe as long as whole rows move together. The risk is filtering to a subset, editing "On hand (new)" for the visible rows, then removing the filter and uploading the full sheet — any row that was hidden during editing still carries whatever "On hand (new)" value was already in the file, which may not be what you intended for that SKU.
How to check before you upload
Confirm your edits actually landed in the "On hand (new)" column, and use the free checker below to see exactly what values will be written before they reach your store.