A.M. Best Co. has affirmed the financial strength ratings (FSR) and issuer credit ratings (ICR) of the insurance subsidiaries of UnitedHealth Group Incorporated (UnitedHealth) (Minnetonka, MN) [NYSE: UNH]. Additionally, A.M. Best has upgraded the FSRs to A (Excellent) from A- (Excellent) and the ICRs to “a” from “a-” for the following subsidiaries of UnitedHealth: Health Plan of Nevada Inc. (Las Vegas, NV) and Sierra Health and Life Insurance Company Inc. (Los Angeles, CA). Concurrently, A.M. Best has affirmed the ICR of “bbb+” and debt ratings of UnitedHealth. The outlook for these ratings is stable. A.M. Best also has assigned debt ratings of “bbb+” to $625 million 0.85% senior unsecured notes, $625 million 1.4% senior unsecured notes, $625 million 2.75% senior unsecured notes and $625 million 3.95% senior unsecured notes all issued on October 17, 2012 by UnitedHealth. The outlook assigned to these debt ratings is stable. Additionally, A.M. Best has withdrawn the FSR of A (Excellent) and ICR of “a” of PacifiCare Life Assurance Company (Denver, CO), as the company is inactive. The rating affirmations for the organization reflect its premium growth, strong earnings, highly liquid assets, ability to adjust to market changes and high degree of technological innovations. These strengths are further supported by the significant market presence, diverse non-insurance operations and financial strength of UnitedHealth. The organization has a wide geographic reach and a diversified portfolio, which includes commercial, Medicare and Medicaid managed care products. UnitedHealth also continues to expand its profitable non-regulated businesses and its share of non-regulated earnings remains significantly higher compared to its peers. Furthermore, UnitedHealth’s non-regulated subsidiaries are well positioned for continuous revenue growth. Non-regulated earnings enhance UnitedHealth’s financial flexibility by contributing to its already strong interest coverage as well as reducing its reliance on dividends from its regulated subsidiaries.