Internet Retail raises free shipping minimum to $35

Getty Images customers will need to spend more money on the site in order to qualify for free shipping.

The online retailer raised the minimum order size needed for free shipping to $35 from $25. The change, made Monday, comes ahead of the busy holiday shopping season.

Amazon is pushing customers to sign up for its Amazon Prime service, which costs $79 a year. Members receive free two-day shipping on millions of items on the site.

(Read more: Amazon state tax ruling heads to Supreme Court)

In a post on its website, Amazon said that it's the first time it has increased its free shipping minimum in more than a decade.

—By The Associated Press