Usually it will, but it entirely depends on the item! Your best bet is to call Costco and ask them if they will have it back in stock soon, some items are gone for a couple of months but then come back, and other items they stop selling, but most of them will be back.
Sometimes they will not restock items that do not sell well. It's highly dependent on what you are looking for. You are normally safe with most food items and electronics, but clothing, books, and seasonal items might be in question. It would be best to call costco to verify about any item.
Does it ever! Boy oh boy do they restock things that are unstock. Reminds me of a time I was at Costco Wholesale and found out they did not have my hunny bunches "instock" ..... so I went back a week later there they were!
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