Allowed for Backorder ??

i noticed that some products say “Allowed for Backorder” and others do not. does this mean that if they dont say this once you are out of stock that item will no longer be available ?

If not, then what makes a product “Allowed for Backorder” or not ,what is the reason for putting this on certain products listings.

Whether or not a product is allowed for back order depends on several factors and is decided on a product-to-product basis.

If a product is not backorderable and it goes out of stock than it is essentially not available until we get more in stock. For most products, however, you can click the “Auto-Notify” button to receive an email when that product does get back in stock.

Products that are permanently no longer available will be removed from the site altogether.

I hope this answers your question!