SM Energy Co.

Will offer a series of senior unsecured convertible notes due 2021. Underwriters will receive a 30-day option to purchase up to $15 million additional notes. Net proceeds will pay the cost of capped-call transactions with underwriters; and the remainder will pay a portion of the purchase price for acquisition of all of the outstanding membership interests of an entity holding undeveloped leasehold interests, producing wells and associated infrastructure assets in the Midland Basin from Rock Oil Holdings LLC. If this acquisition does not close, remaining net proceeds will support general corporate purposes.Notes will mature on July 1, 2021, unless earlier converted or repurchased. Wells Fargo Securities, BofA Merrill Lynch and J.P. Morgan are joint book-running managers.