This would pit the e-commerce giant against the likes of FedEx and UPS.
The service is called "Shipping with Amazon" and will see the tech giant picking up packages from businesses and delivering them to customers, the WSJ said, citing people familiar with the matter.
Amazon's business delivery is expected to roll out in Los Angeles in the coming weeks with third-party merchants that sell goods via its website. More cities are to follow.
The U.S. firm will eventually roll this out to other businesses with Amazon planning to undercut UPS and FedEx on price, according to the WSJ.
UPS said it is still a partner of Amazon.
"UPS continues to support Amazon and many other customers and we don't make comments about their business strategies or decisions regarding their utilization of UPS services," a spokesperson for the company told CNBC in an emailed statement.
Read the full Wall Street Journal article here.