Global mergers and acquisitions are on pace this year to hit the highest level on record, thanks to a buying spree from companies on the hunt for growth.

Takeover-deal announcements would reach $4.58 trillion this year if the current pace of activity continues, according to data provider Dealogic. That tally would comfortably exceed the $4.29 trillion notched in 2007, a record year for deal making.

There...