A municipal security’s credit rating is assigned by a Nationally Recognized Statistical Rating Organization (NRSRO) and measures the probability of the timely repayment of principal and interest. The factors upon which the rating agencies base their credit ratings vary with each type of issue.
Municipal securities can receive a rating at the time of issuance, are periodically reviewed, and such rating may be changed or withdrawn to reflect the change in the state of local government’s credit position. There are no requirements for municipal securities to be rated or, if a security has received a rating, to be rated by all rating agencies. Read more about understanding credit ratings.
In November 2011, the MSRB began making available on the Electronic Municipal Market Access (EMMA®) website current credit rating information for municipal securities from Fitch Ratings and Standard and Poor's.