On 5 November 2018, the Bulgarian Ministry of Finance published for the first time a proposal for introducing mandatory transfer pricing documentation requirements in the country. This article provides a detailed overview of the proposed new rules and more specifically in which cases the taxpayers will be obliged to prepare transfer pricing documentation, the information that should be included, the deadlines for preparation and updates as well as the sanctions for non-compliance with the requirements. The information in the article is valid as at 5 February 2019. It should be taken into account that the initial proposal could be changed during the legislative process before the final texts are published.