The Bhutan visa allows you to remain in Bhutan for a maximum of 90 days from the date of entry. Extension of visa is available.

You can extend your visa while you are in Bhutan. Provided the extension is applied for before the original visa or permit expires. You can extend your stay via the online visa application portal, using the same log-in details that were used to process your original visa. The fees for processing your extension application, and daily SDF (USD 200 per people per night) for the duration of your extended stay, will be payable via the same portal. Read more about visa apply by 2023 updated Bhutan Visa Online Application Guide

Source : bhutan.travel (Sept. 2022)

Here is a Bhutan e-visa from our group for your reference:

Bhutan E-visa

As mentioned, Indian, Bangladeshi and Maldivian don't need a pre-applied visa to enter Bhutan. But all nationals need to bear passports with a minimum of 6 months' validity before the travel date. Especially for Indians, they're free to enter Bhutan by air or land because of the free movement treaty between Bhutan and India.

Any of the following documents are applicable upon entry:

1.Indian Passport

2.A Voter ID card with photograph

3.Identification Slip issued by the Indian Consulate Office in Phuentsholing upon presenting proof of Indian citizenship.

2.Official Guest of the Non-Governmental Organization
•Forwarding letter from the Head of Organization
•Approval letter from the Ministry of Foreign Affairs
•Filled up visa applications(need to filled up by the guests only)
•Passport photocopy of the visitor

3.Official Guest of the Corporate & Autonomous Agencies
•Forwarding letter from the Head of Institutions addressed to Dy. Chief of Protocol
•Approval Letter from the Chairman
•Filled up visa application forms(need to be filled up by the guests only)
•Passport photocopy of the guest

4.Official Guest of the Sport Association
•Forwarding letter from the General Secretary addressed to Dy. Chief of Protocol
•Approval Letter from the President
•Filled up visa application form (need to be filled by the guests only)
•Passport photocopy of the visiting guests

5.Long Term Foreign Expatriate's Guests
•Forwarding letter from the concern organizations addressed to Dy. Chief of Protocol
•Tenure of Host(Only long term are allowed to apply)
•The host must complete six months prior to their arrival in the country
•Filled up personal guest application
•Filled up visa application form
•Passport copy of the visitor as well as the host
•Dependents of expatriates shall be allowed to join them in Bhutan for a period not exceeding the duration of their assignment
•Term "Dependents" is defined to include the spouse and children of the expatriates
•The duration of the stay of the guests do not exceed one month

6.Official Guests of the Private Organizations
•Forwarding letter from the MoEA
•Filled up visa applications form
•Passport photocopy of the guests

•If the Government or any Private organizations wants to employee an foreigner, approval must be sought from Chief Labour Officer, Department of Labour with valid work permit.
•The visa forms can be downloaded from the MoHCA website.
•The maximum period of days required for processing visa is two working days; hence all the applications applying for visa should be submitted before two days from the prior date of arrival of the guests.
•The visa clearance from the visa section should be collected only during the afternoon by 2: 00 P.M. to 5: 00 P.M.

Nationals exempt from advance visa to enter Bhutan:
•Bangladeshi, Maldivian & Indian nationals do not require visa while coming to Bhutan.
•Thai and Swiss nationals holding official and diplomatic passports while coming to Bhutan do not require visa. The visa will by stamped upon arrival at the Paro International airport or any other port of entry by Immigration authorities. But those carrying ordinary passports need to process Bhutanese visa in advance. 

Gratis Visas:
•Only those Officials carrying diplomatic, UN & official passports will be issued gratis visas.
•If there is a MoU signed indicating some points about the free charges, then the visiting guests will be issued gratis visas.

Extension of Visa for the Visiting Guests:
•If the guest has to stay back for more than three days, then the concerned Ministry/Organization etc need to write a letter addressed to Dy. Chief of Protocol. The letter must mention the genuine reasons for the extension.
•A copy of earlier visa which was issued by the Immigration.

What is the Photograph Requirements for Bhutan Visa？Your passport application for Bhutan Visa must be affixed with a recent passport photograph (not more than six months old). The size of the photograph should be 45 mm x 35 mm with your facial image taking up 70 to 80 % of the photograph, taken with a white background and without border.

The Photograph Requirements for Bhutan E-visa 2023

The photograph for Bhutan Visa must:

1. Show you looking directly at the camera. No looking over one shoulder (portrait style).

2. Show eyes open and clearly visible. If you wear glasses there should be no flash reflection, no tinted lenses and the frames should not cover any part of your eyes.

3. Be in sharp focus and clear – no shadows.

4. Be of high quality with no ink marks or creases. Photographs taken with a digital camera must be printed on photo-quality paper.

5. Be clean with no smudge marks.

6. Be glued and not stapled or pinned to the application form.

Your passport photograph for Bhutan E-visa is the primary form of identification and following these minimum ICAO standards would facilitate proper identification at immigration checks while avoiding the need for the Passport Section to ask you to resubmit your photograph.

PHOTO OK:(Background white,and facial image covering around 70% of the photograph)

PHOTO NOT OK: (Background not white,frame of glass over the eyes and facial image small)