Amazon Prime members in the United States will soon enjoy free delivery for grocery purchases above $100 via Amazon Fresh, a drop from the previous $150 threshold, according to an internal document.

The change, set to be implemented this week, was confirmed by Amazon's (AMZN  ) worldwide VP of Amazon Fresh, Claire Peters, who noted that the adjustment would take effect on Thursday afternoon. The current fee structure, which sees orders between $100 and $150 incurring an additional $3.95, will remain the same for other delivery fees, as reported by Insider.

"Prime membership continues to be an enormous value and this change will save members even more on grocery delivery fees, while also allowing them to enjoy added savings, convenience, and entertainment with Prime," Peters said.

Despite its continued ambitions in the grocery space, Amazon has experienced minimal growth. Amazon's market share was just 1.2% of the US grocery market in 2021, starkly contrasting with Walmart's 25% and Kroger's 8% share, as per Euromonitor.

This shift happens to be a swift change from the new fee structure Amazon began imposing in February, hinting that the e-commerce giant may have discovered better cost efficiencies.

Amazon provides grocery delivery services to Prime members in over 3,500 cities and towns across the U.S. The company is also mulling over a separate, standalone grocery subscription service for Prime members.