Trunk will build its own inventory and stock levels from your listings based on the first unique SKU it sees. Then any future SKUs that match will have Trunk's own stock level initially synced to it.
So that means you'll want to first connect the sales channel that has the most accurate stock levels if you're just starting out with Trunk. For example, say you have these 2 listings:
Sales channel | SKU | Stock |
Etsy | ABC | 25 (accurate) |
Shopify | ABC | 27 |
You'll want to connect Etsy first since it has the more accurate stock level and then wait for Trunk to build its own inventory from the Etsy listing with a quantity of 25. You can verify once this has been done by searching for the SKU within your Inventory and seeing that it has a quantity of 25. Now when you connect Shopify, Trunk will sync its own quantity of 25 to the Shopify listing.
This concept is also the same for listings that don't have SKUs (or aren't matching) yet. For example, say you have these 2 listings:
Sales channel | SKU | Stock |
Etsy | (blank) | 25 (accurate) |
Shopify | (blank) | 27 |
You'll want to add the SKU first to Etsy since it has the more accurate stock level. Once Trunk picks up on the SKU change, it will build or update its own inventory from the Etsy listing with a quantity of 25. The best way to verify that this has happened is to search for the SKU within your Inventory and see that it has a quantity of 25.
⚠️ Please be aware that there can be API delays. Even though you may have saved the Etsy listing before the Shopify one, what really matters is when Trunk picks up on the changes.
Now when you add a matching SKU to the Shopify listing, Trunk will sync its own quantity of 25 to it.
Once the initial sync has happened, there is no longer a "source of truth". You can change stock on any of your sales channels which Trunk will automatically pick up on and sync to everywhere else in real-time.
Note that if this behavior doesn't work well for you, we do have a way to set priorities for your sales channels, so that one sales channel will always take priority for the initial sync even if the SKU already exists within Trunk. Please reach out to support if you'd like to take advantage of this!