I currently sell there and yes you need upc codes. I get mine pretty cheap , just google upc.net. I love selling on there because they take their fees right away, instead of having to pay at the end of the month.
I'm kind of confused about UPC codes... does every individual item have a different UPC code? Or does each kind have a UPC?
Example: Unscented lard soap has one UPC code and Coffee Soap has another UPC?
or every single bar or the unscented lard soap has it's own UPC?
I've done a little research on UPC codes for my husband's business. I HATE manually counting stuff for his year-end inventory. Yes you would have an individual code for each item. Though I'm not especially fond of this lady, she did a good video when she opened her retail store. I'm not as copy/paste savvy as others here, but you can find a You Tube video at Essential Soap "How to Buy Barcodes and Create Barcode Labels for your Homemade Soap Tutorial" with Essential Soap. Though it's drawn-out, I found it helpful as a primer to UPC codes. How exciting that you are considering going "Big-time" with Amazon!