Instacart has had a busy week.

The grocery delivery service announced an expansion in its partnership with Kroger while rolling out new services with Aldi and BJ's Wholesale Club.

Kroger announced Monday its expanded partnership with Instacart to increase delivery coverage area in 2018.

"As part of Restock Kroger, we are redefining our customers' grocery shopping experience by bringing online and offline seamlessly together," says Yael Cosset, chief digital officer for Kroger. "Having grown our digital sales in 2017 by 90 percent, we continue to accelerate our digital roadmap in 2018 to make shopping with Kroger simpler and more personalized."

Kroger says it plans to add 500 new locations to the existing 1,091 curbside pickup locations. The company currently delivers from more than 870 stores nationwide. 

"With the expansion of our Instacart partnership, it provides Kroger the opportunity to increase our delivery offerings even further and when you combine it with our successful curbside service, it will help us accelerate our ecommerce reach significantly," Cosset says.

Meanwhile, discount grocer Aldi also announced an expansion to its pilot Instacart program.Starting this week, Aldi offers online ordering through Instacart to residents across Chicagoland, Northwest Indiana and as far weest as Rockford, Illinois. Previously, Aldi was testing with  Instacart in Atlanta, Dallas and Los Angeles.

"We are committed to saving people time and money, no matter how they shop for groceries," says Jason hart, ALDI's CEO. "The response to our Instacart pilot was overwhelmingly positive, and with nearly 200 Chicago-area stores, it only makes sense to bring online delivery to this major market."

The expanded partnership with Aldi brings a clear low-price option to Instacart's offerings. 

Instacart also announced it is expanding its partnership with BJ's Wholesale Club to offer same-day delivery nationwide by the end of April.Customers in cities along the East Coast can take advantage of same-day delivery starting immediately.