Trekking permits are required for the Nepal Trekking, those permits can be issued by the government of Nepal and its authorized associated bodies which are regulated and monitored by the government. There are three types of Nepal Trek Area divided by the Nepal government;
1. Normal Area: No Need for Trekking Permits but might need TIMS Card.
2. Directed Area: Need Trekking permits but can go individual and can by you. National Park, Conservation Area, and Protected Area. For that area, permits can easily obtain at the Nepal Tourism Board office in Bhrituktimandap, Kathmandu, and Pokhara. For this, you need your passport copy with a validated visa for the entire trip and 2 PP size pictures. Those permits can be organized before your arrival when you provided your passport copy and pictures.
3. Controlled Area: Need a special permit for certain days, must be at least two trekkers, through the authorized trekking agency, and need to take at least one professional Guide. Can’t go individually. As this is restricted area permits, you need to join a trekking agency for this trek, they do everything for you. While obtaining these permits, you need to go Nepal Immigration office at Dilibazar, Kalikasthan, Kathmandu after applying for all required documents online with along your original passport and USD cash for the permits fee. Normally, controlled area Trekking permits is not possible to organize before your arrival and for single trekkers, however, there are high chances to find ghost trekking partner. Go through the more details about Nepal Trekking Permit and Fee.