I am a citizen of the USA and am considering the trip to Bulgaria in 2020. As a US citizen with a valid US passport (valid until 2026), do I need a visa to enter and tour Bulgaria? I have looked at the Bulgaria Foreign ministry website and it leaves me somewhat confused. If I need a Visa, when and where do I apply/obtain it? At the airport on arrival or in advance of traveling to Bulgaria? And the cost? Thanks.
According to this information of the Bulgarian Embassy in the USA you don't need a visa.
No, you don't need a visa to enter Bulgaria as a tourist and stay for up to 90 days. (Our tour members have been doing this for years.) See also the US State Department's notes.
Yes, your US passport is all you’ll need get in for a visit, and you’re set as long as you have so much time when you leave that your passport will still be valid. I flew from the USA and was going to be departing Bulgaria with less than 30 days left on my passport, thinking I was efficiently squeezing just about every possible travel day out of it. And although I was let out of the USA for my connecting flight in London, the London airport folks wouldn’t let me on the plane to Sofia, saying Bulgaria wouldn’t let me in with so little time left on my passport. I had to scramble to get a new passport at the American embassy in London to actually get to Bulgaria, and I’ve never let that happen again, renewing my passport 6 months before the old one expires. Enjoy your trip in 2020, plus the (almost) 6 years left on your passport when that trip’s finished!