CNET

Retail giant Amazon apparently doesn't want Walmart to offer a better deal on shipping.

Without promotion, Amazon has lowered the minimum required for free US shipping from $49 to $35, something The Verge noticed this weekend and reported on Sunday. That threshold applies to shoppers who are not Prime members, and the minimum for free shipping on books remains $25.

An Amazon spokeswoman confirmed it "recently" lowered the minimum price for free shipping, but decline to specify when the change took place or why it made the move.

However, competitor Walmart, just last month, ended its similar membership program while at the same time lowered its website's minimum for free shipping to $35. It also sped up those deliveries to two days. Amazon's free shipping offer is for regular, five- to eight-day shipping (unless you sign up for Prime.)

It's all part of an apparent battle for online shoppers who have yet to join Prime. An estimated 44 percent of US households subscribe to Prime, making them far more likely to shop regularly with Amazon.

Amazon raised the minimum amount for free shipping a year ago to $49 from $35. It upped the price to $35 from $25 in 2013.

Updated at 4:40 p.m. PT with comment from Amazon.

Correction, Feb. 20 at 8:20 a.m. PT: Amazon's new $35 minimum is for free standard shipping, not two-day shipping.