The easiest subject line to overthink, because the reader already asked for this update. Name the product and get out of the way; the news is the whole message.
63.1% average open across 428,895 OnVoard back-in-stock sends, the highest open rate of any email type we send.
Aggregate across all OnVoard merchants, not a promise for your store. Back In Stock earns this because the reader already asked to be told before any subject line was written; wording did not manufacture that intent, it just has to not waste it.
The easiest subject line to overthink, because the reader already asked for this update. Name the product and get out of the way. Every line below is scored against this exact profile in the subject line tester.
Grouped by purpose. Every line scores 85 or higher against the back in stock profile, with no red checks. Click "Test this" to see why, or to try your own version of it.
These are the subject lines. Back In Stock is its own OnVoard app: a shopper asks to be notified, and the alert goes out the moment the item is back, no workflow to build.