EPM began the process to register with the Stock Market in 1997. Since then, as provided by Resolution 400 of 1995, the company has had credit ratings for all the securities it has issued to date. In addition, since 2003, as provided by Decree 610 of 2002 issued by the Ministry of Finance and Public Credit (Ministerio de Hacienda y Crédito Público), Empresas Públicas de Medellin has a credit rating. In both cases, EPM has received the highest annual ratings.
Since 2007, EPM has received its Foreign Issuer Default Ratings IDRs from Fitch Ratings. In mid- 2009, when the Company entered the international securities market, Fitch Ratings and Moody´s Investor Service assigned investment grade ratings: the foreign issuer Default Ratings and the international bond issuances.