On this page there’s 3 highlights (view in Baymard Premium) outlining what Costco are doing right and wrong.
(Tip: use the arrows above or on your keyboard to navigate all 177 address validator examples.)

The screenshot was taken on June 30, 2016 and depicts Costco’s Address Validator. In total, we’ve reviewed 65 of Costco’s page designs. To see them all, visit the full Costco UX case study.