Walmart on Wednesday said it will expand its online grocery delivery service to serve more than 100 metro areas across the country. By the end of the year, the option will be available to more than 40 percent of US households, the retailer said.

The service is available today in just six markets.

Walmart in 2016 partnered with ride-hailing services Lyft and Uber to deliver groceries. Based on the language used in today's press release, it sounds as if Walmart will be expanding its use of these services rather than hiring more of its own delivery drivers.

Many grocery providers offer services that allow customers to shop online and pick up their orders in-store but far fewer provide a delivery service. AmazonFresh is perhaps the most well-known grocery delivery service yet even still, it's only available in select major metropolitan areas.

I've personally utilized an online shopping service with local pick-up and can attest that it's a real time-saver. Having a service take the extra step of delivering my order right to my door sounds even more appealing. Walmart offers a similar pick-up service at 1,200 locations across the country with plans to add an additional 1,000 stores to the mix this year.

Walmart's delivery service carries a $9.95 fee with a minimum order of $30. In most cases, groceries can be delivered to customers as soon as the same day.

For a limited time, you can use the promo code FRESHCAR to get your first order delivered free of charge.