MarkWest Energy Partners LP (NYSE: MWE) and its subsidiary, MarkWest Energy Finance Corp., closed its public offering of US $1 billion of 4.5% senior unsecured notes due 2023 priced at par.

Net proceeds will be used to fund the redemption of all of its outstanding 8.75% senior notes due 2018, and a portion of its 6.5% senior notes due 2021 and 6.25% senior notes due 2022, with the balance of such proceeds to be used to fund the partnership’s capital expenditure program, for general working capital, and for other general partnership purposes.

Barclays, BofA Merrill Lynch, Citigroup, Goldman, Sachs & Co., J.P. Morgan, Morgan Stanley, Natixis, RBC Capital Markets, SunTrust Robinson Humphrey, UBS Investment Bank, US Bancorp, and Wells Fargo Securities were joint book-running managers.

MarkWest Energy Partners LP is a master limited partnership headquartered in Denver that is engaged in the gathering, transportation, and processing of natural gas; the transportation, fractionation, marketing, and storage of NGLs; and the gathering and transportation of crude oil.