Amazon.com Inc has raised its free-shipping threshold for orders from non-Prime customers to $49 from $35 in the United States.
Orders of books worth $25 or more will, however, be eligible for free shipping, according to the shopping website.
Amazon has been spending on rolling out several new services for members of its $99-a-year Prime loyalty program, including one-hour delivery and original media programming, to attract customers in a highly competitive online shopping market.
The company’s shipping costs rose more than 18 percent to $11.5 billion last year.
The online retailer is also quietly inviting drivers for its new “on-demand” delivery service to handle its standard packages as it looks to speed up delivery times and reduce costs.