Bond rating firms like Standard & Poor’s (S&P), Moody's, and Fitch use different designations, consisting of the upper- and lower-case letters "A" and "B," to identify a bond's credit quality rating. "AAA" and "AA" (high credit quality) and "A" and "BBB" (medium credit qual...
Both A+ and A1 represent the fifth-highest rating a debt issuer or a debt instrument can receive. At Moody's, the A1 rating comes after the Aaa, Aa1, Aa2, and Aa3 ratings. The A rating itself denotes that the bond (or whatever security is being rated) is "upper-medium grade and ...