1. It is the Constitution alone that defines the Constitutional Court powers.
The Constitution provides that no power of the Constitutional Court shall be vested or suspended by a law.
Art. 149 para 1 of the Constitution lists in 8 points the Constitutional Court competencies.
Other Constitutional provisions complete the Constitutional Court competencies.
Art. 149 para 1 subpara 1 vests the Bulgarian Constitutional Court with the competence to provide binding interpretations of the Constitution. There is a difference between this interpretation competence and the case interpretation when the Constitutional Court exercises its other competencies. While binding interpretation seeks to extract normative sense of the interpreted Constitutional provisions, it is not charged with the settlement of a specific constitutional dispute.
The second substantial powers of the Court is to rule on complaints to the constitutionality of the laws and other acts of the National Assembly and the decrees of the President. This control is in fact the Constitutional Court’s major competency and the greatest number of instituted and resolved cases relate to it. It is post-promulgation control as it extends on legal acts that have already been promulgated in Darzhaven vestnik (The State Gazette).
 
There is only one instance when the Bulgarian Constitution provides for pre-promulgation control by the Constitutional Court: when the Constitutional Court rules on the compatibility between the Constitution and the international instruments concluded by the Republic of Bulgaria prior to their ratification.
Also, the Constitutional Court may rule on the compatibility of domestic laws with the universally recognized norms of international law and the international instruments to which Bulgaria is a party. The Constitutional Court is empowered to rule on competence disputes between the National Assembly, the President and the Council of Ministers and between the bodies of local self-government and the central executive branch of government.
Further, the Constitutional Court rules on challenges to the constitutionality of political parties and associations, on challenges to the legality of the election of the President and Vice President or of a Member of Parliament. The Constitutional Court decides on impeachment brought by the National Assembly against the President or the Vice President for treason or violation of the Constitution.
 
2. In addition the Constitution vests the Constitutional Court with the power to establish facts of constitutional relevance. These are: the resignation of the President or Vice President or their permanent incapacitation; ineligibility or incompatibility of Members of Parliament; resignation of a Constitutional Court justice, actual inability of a justice to perform over a period of more than one year; incompatibility with offices and activities under Art. 147 para 5 of the Constitution.
The Constitution vests the Constitutional Court with a competence which goes beyond fact-finding: this is the stripping of a Constitutional Court justice of his immunity. Doing that the Court finds facts and also assesses facts and passes its ruling on the basis of this assessment.