Costco announced Tuesday that it has acquired logistics firm Innovel Solutions for $1 billion in cash in a bid to boost the warehouse-club operator’s online sales.

Innovel was a subsidiary of Transform Holdco — which operates Sears and Kmart stores — and provides “final mile” delivery and installation of bulky items such as appliances, furniture and TVs for Sears and other retailers in the United States and Puerto Rico, Costco said. Issaquah-based Costco, with 786 warehouse clubs worldwide, has been an Innovel customer since 2015.

“We have had a great relationship with Innovel and share a philosophy of taking care of our members,” Costco CEO Craig Jelinek said. “We believe the acquisition will allow us to grow our e-commerce sales of ‘big and bulky’ items at a faster rate.”

Innovel, with a workforce of 1,500 people, operates 11 distribution centers and more than 100 centers for final delivery. It will continue to serve Sears and other retailers in addition to Costco.

The acquisition is Costco’s largest since merging with Price Club in 1993, according to the Wall Street Journal.