Bulgaria introduced International Accounting Standards (IAS) on January 1, 2003, for certain companies. This was done two years ahead of European Union countries. The companies for which IAS are mandatory as from the beginning of 2003 include Bulgarian banks, insurance companies, social security institutions, and investment and public companies.
They are now required to prepare their entire monthly, quarterly, and six-monthly accounts according to IAS.

IAS are mandatory from 2005 for all companies in Bulgaria, including small and medium-sized enterprises. This is in contrast to EU countries, where only public companies are obliged to use IAS from 2005. Questions have been raised about whether SMEs in Bulgaria will have the capacity to comply with the requirements of using IAS. Elsewhere in Europe, there has been major resistance among small and medium enterprises to being required to use IAS. Media reports in early 2003 pointed out that the Bulgarian-language version of IAS runs to 800 pages. An English-language version has been compiled by a group of experts.

The introduction of IAS in Bulgaria was regulated by the new Accounting Act, which was approved by Parliament towards the end of 2001.
In January 2002, the Government adopted 37 new National Accounting Standards, compliant with the IAS. Of these, 32 standards refer directly to the IAS and five are Bulgarian standards because they have no equivalents in the IAS list.

A Government ordinance regulates the use of IAS, and flows from the provisions of the Accounting Act.
According to the Accounting Act, the reporting period is January 1 to December 31.

Due its specific political and historic past, the contemporary accounting standards were first introduced in Bulgaria in 1991. Because of the country’s state ownership regulations under communist regime, any financial data was primarily used for controlling the costs and prices of production and protecting the property rather than presenting the information to outside investors. Nowadays, the existing accounting standards in Bulgaria are practically the American accounting standards. Ever since 1991, Bulgaria has been developing its accounting legislation in accordance with Anglo-American and the European system, accepting principles step by step, moving closer at times to either one. In 1998, Bulgarian Accounting Law started changing in conformity to Anglo-American countries, predominately adopting the IAS. In 2002, it was concluded that Bulgaria does not have a specialized economy, and the country took the final step into entirely basing its Accounting Law in conformity to the IAS. The European countries also accepted the idea that IAS can become a common basis for the preparation of financial reports and stated that from the beginning of 2005 these standards are to be used for the preparation of financial reports by all European companies whose securities are traded on the stock exchanges.