The distance from Bagdogra to Phuentsholing is 140 km and takes about 3.5 hours. The ride is picturesque, especially if you start early morning, you get to see the sun rise amidst tea gardens.Your entire ride is in West Bengal, do not miss the poori sabzi, samosa, tea and rasogullas at numerous eateries on the road. There are a lot of ATMs near the Indo-Bhutan border and better to carry cash as majorly hotels in Bhutan prefer cash. The preferred denominations are 100 and 500 and Indian currency is happily accepted however many government places have clearly written that they won’t accept Indian 500 and 2000 notes. Since ours was an early morning taxi , it cost us INR 3000, otherwise you can bargain and get a ride for INR 2500 also.
I reached the permit office at 10 am and was done by 11:30 am. You need a photograph, your itinerary, proof of stay in Thimphu and Paro. You can also download the form online. The permit here is only for Thimphu and Paro is not given for more than 7 days. After that you have to get it extended extended at the immigration office in Thiumphu. You also need to apply for separate permit for Punakha and other places at Thimphu again by producing an itinerary and accommodation proofs. I was travelling with my wife and got the permit easily, however if you are solo or gang of friends, you will need to convince the authorities.
The distance of Thimphu from Phuentsholing is 170km and takes 5 hours in a taxi and 8 hours in a bus. We were carrying one bag pack each and easily took shared taxis everywhere in Bhutan. The shared taxi fare from Phuentsholing to Thimphu is 750 per person and mostly taxis are 5 seaters.
Please find below the shared taxi costs in Bhutan. Also note that Chele la pass and Dochula pass comes during the way and you can do it in shared taxi by letting the driver know before hand and paying extra.
Phuentsholing to Thimphu- 750/person
Thimphu to Paro- 200/person
Paro to Haa (not via Chele La)- 350/person