An overview of the ratings per ratings agency

Credit ratings

 

Moody’s Standard & Poors Fitch
Investment grade Strongest Aaa AAA AAA
Aa AA AA
A A A
Baa BBB BBB
Non-investment grade Weakest Ba BB BB
B B B
Caa CCC CCC
Ca CC CC
C C C
C D D
  1. These credit ratings are reflective of obligations with long-term maturities 

Source: Reuters. Treasury Today (http://treasurytoday.com/2018/09/time-to-get-rated-ttb2b)