The best source for both individual bars and "lots" (bulk packs). You can find various sizes, including the common 1 oz travel size and 1.25 oz bars.

Because it is not a "core" consumer product, you won't typically find it on the shelves at major pharmacies like CVS or Walgreens, but there are several reliable ways to get it online. Where to Buy

It is significantly more cost-effective to buy a "lot" of 10 or 20 bars rather than a single bar, as shipping costs often exceed the value of a single soap.

A retailer that specializes in hotel-quality bedding and bath products, frequently carrying Neutrogena bar soap lots. Buying Tips

Periodically lists the soap through third-party sellers, often in multi-packs or sets. Specialty Liquidators: Petit Maple: Often stocks 24-packs of the 1 oz bars.