With Bulgaria's entry into the EU in 2007, Bulgaria's visa requirements have been upgraded to meet EU requirements. Basically, entry into Bulgaria is now as (relatively) simple as entry into any EU Member State.

A U.S. passport is required for U.S. citizens who are not also Bulgarian nationals. As a U.S. citizen, you are authorized to stay for a total of 90 days within a six-month period without a Bulgarian visa. This law is strictly enforced. You can file an application to extend your stay beyond the original 90 days for urgent or humanitarian reasons, but the application must be submitted to regional police authorities no later than five days prior to the end of the original 90-day period. Travelers who have been in the country for 90 days and then leave will not be able to re-enter Bulgaria before the six-month period expires. Travelers using official or diplomatic passports must secure visas prior to arrival. Please plan and apply for your visa early. Upon entering the country, Bulgarian immigration authorities request that all foreigners declare the purpose of their visit and provide their intended address.

If you intend to live or work in Bulgaria for more than 90 days within six months (or more than six months within a year), you must obtain a “D” visa prior to arrival. As of July 2008, U.S. citizens must apply for a “D” visa at a Bulgarian Embassy/Consulate in the country where they are legally resident. If you wish to obtain a “D” visa while already present in Bulgaria -- having entered as a tourist, for example -- you will have to leave Bulgaria in order to apply for a visa at a Bulgarian embassy or consulate in the United States. U.S. citizens residing in the United States should apply at the Bulgarian representative office (either the Embassy or a Consulate) nearest their home.

The Bulgarian authorities do not consider presentation of a copy of the passport sufficient for identification purposes. Visitors should carry their original passports with them at all times; however, this is not a requirement for U.S. citizens who hold residence permits for Bulgaria. A U.S. passport card is also recognized as a proof of citizenship and identity, but is not accepted for use for international air travel; it can be used only to enter the United States from Canada, Mexico, the Caribbean, and Bermuda at land border crossings or sea ports-of-entry.