Jet.com
National online retailers such as Jet and traditional retail behemoths such as Walmart (which purchased Jet in 2016) are also rapidly expanding their grocery delivery options. Jet.com started as a members-only site intended to compete with warehouse clubs such as Costco, and with Amazon Prime memberships. It has since waived the membership fee and added two-day delivery while often undercutting Amazon prices, particularly on fresh groceries. Membership is free.