Sage is just the latest target of similar campaigns by NetSuite, which have also focused on Salesforce.com and SAP. The new offer is for users of any Sage products and covers the U.S., Europe and Asia-Pacific.

NetSuite's offer especially targets companies that were looking at Sage's Sage Live on-demand accounting software. Sage recently the Sage Live beta, to fix security issues.

NetSuite listed some customers in the U.S. and U.K. who it said have already switched from Sage to NetSuite. But a Sage executive scoffed at the announcement.

"This is not a new tactic," said Himanshu Palsule, executive vice president and general manager of business management at Sage North America. "They've done this before and we haven't seen much traction. It's a sales promo."

NetSuite seems to be targeting much larger customers than Sage, he said.