Nationals from India and Bangladesh do not need a visa.
Everyone else needs to arrange a visa before arriving. And you need to book a tour.
To obtain a Bhutanese visa, you need the following:
-Bhutan visa application form x 3 copies duly filled
-2 passport-size photographs
-Photocopy of the passport
For private visitors, a sponsorship certificate form must be filled in by the sponsor.
Prices start at US$200 per day per person and can take up to one month to process.
When entering Bhutan, you will receive a visa valid for only 2 weeks from Paro airport.
The Kingdom Of Bhutan Visitor Information