Investors will be watching for indications that by encouraging customers to place larger, more frequent purchases, Amazon’s (AMZN.O) aggressive growth of same-day delivery services contributed to an improvement in its profit margin in the third quarter.

In at least 90 locations, same-day delivery is now free for Prime members and $9.99 for non-members. The company made significant investments in logistics in 2020 and 2021 to expand the availability of its 2015 launch of same-day delivery.

Investors and analysts expect gross profit margins to increase to 47.37% from 47.37% last year when Amazon announces earnings on Thursday, according to LSEG.

Fast delivery “drives more frequency to Amazon’s website,” according to Arun Sundaram, a CFRA analyst.

It encourages Amazon to provide bigger basket sizes. People are finding it incredibly handy to go on Amazon and buy things like paper towels, food, or packaged products now that the company is launching many more everyday essentials,” the spokesperson added.

Amazon crams its top 100,000 goods into its same-day delivery hubs. The firm said in April that it had finished restructuring its fulfillment network, breaking the country into eight zones to reduce delivery times and distribute goods to customers more quickly.

According to Sarah Mathew, vice president of worldwide delivery experience at Amazon, “we find that when we open up same-day (delivery), you generally see customer engagement go up and purchasing go up” in a recent interview with Reuters. “But the lift of how much it goes up varies from product to product.”

According to Mathew, the business will keep constructing fulfillment facilities to increase same-day delivery. Additionally, same-day delivery increases visitors to Amazon.com. This puts the company in a better position to increase its advertising income, which has increased by at least 20% per quarter in 2022 compared to this year.

According to Columbia Threadneedle expenditures analyst Mari Shor, because of their expenditures in fulfillment facilities, storage, and quick delivery, Amazon and its main rival, Walmart.com (WMT.N), have become the go-to sites for online shopping.

According to Sundaram, the expansion of e-commerce depends on same-day and one-day delivery, which will boost Amazon’s profits over the next three to five years, together with advertising income.

Wedbush analyst Scott Devitt stated that he believes Amazon’s quick delivery would help it hold onto or increase its market share while keeping up with more recent e-commerce competitors, including Shein, Temu from PDD Group, and TikTok Shop from ByteDance.

“Next-day and same-day delivery is going to be much more beneficial to Amazon’s volume growth than any degradation that we see from Temu,” Devitt stated.

An LSEG estimate states that analysts anticipated Amazon’s North American retail division to generate $85.9 billion in sales in the third quarter, a 9% increase over the previous year.

In contrast, experts predict that when Walmart releases its third-quarter earnings in November, e-commerce revenue will have decreased by 1%.