Visitors can travel to Bhutan through all inclusive package tours only for which tariff is set by the Royal Government. The Governmentís fixed tariff includes services of accommodation, transport, guide and meals.
    All tours must be booked through Tour operator and entire land arrangements made by the same agent.
  For all cultural tours the booking must be complete at least 04 weeks in advance but for tours during festivals 08 weeks advance confirmation is required. Festivals held in autumn and spring are peak time for the tourists and without early reservation it can be very difficult to confirm flights and hotels.
For trekking groups, it is important to do booking at least 08 weeks in advance as it requires plenty of planning.
  Visa is required for traveling to Bhutan and it is processed and arranged by Eco Tours & Treks.
  All information as mentioned in visa form shall be forwarded to us at least 03 weeks prior to date of travel to process it with concerned authorities. Alternatively copy of visa form can be filled up by tourists and mail/fax to us to arrange visa.
  Actual visa is stamped on arrival in Bhutan while it is cleared in advance and a visa clearance number issued.
  Visa clearance number is also required while issuing Druk Air tickets. For travelers, entering the country by surface through Phuntsoling (the border town in south of Bhutan) the visa is stamped on arrival and clearance number is forwarded to Foreign Ministryís Office at Phuntsoling for reference
  Two copies of original passport size photographs are required on arrival.
Visa fee is US$ 20 per person for 14 days which can be further extended with additional fee of US$ 15.
  For all FITís / GITís traveling during festivals, visa particulars must be sent at least 06 weeks in advance as festivals are peak time for tourists and all tour formalities are required to be completed well in advance.

You can download the visa form from here [Visa Form]