SAN FRANCISCO — Instacart Inc., an online grocery delivery service, has entered greater Atlanta. Shoppers in the market can now order groceries from a Kroger Co. or a Costco Wholesale Corp. store and have them delivered in an hour for $5.99 on orders above $35, the company says.

Instacart Inc., an online grocery delivery service, has entered greater Atlanta. Shoppers in the market can now order groceries from a Kroger Co. or a Costco Wholesale Corp. store and have them delivered in an hour for $5.99 on orders above $35, the company says.

Two-hour delivery costs $3.99.

Additional stores will be added in the coming weeks. Company officials note that customers can combine items from multiple stores into one order, and a customer does not have to be a Costco member to order from Costco on Instacart.

Atlanta is the 12th city served by San Francisco-based Instacart. The company was created two years ago. Last month, it announced it had received $44 million in venture capital from Silicon Valley investors.