Yes. Both Lachen and Lachung are located in restricted areas of North Sikkim and require special permits. These are arranged by your tour operator and require valid ID proof (Aadhar card, voter ID, or passport for Indian nationals).
The ideal time is between March to June (spring/summer) for flowers and greenery, and October to December for snow and clear mountain views. Avoid monsoon season (July–September) due to landslides.
Network connectivity is very limited. BSNL and sometimes Airtel may work with weak signals. Wi-Fi is mostly unavailable in Lachen and Lachung, offering a true digital detox.
No ATMs are available in Lachen or Lachung. It's advisable to carry sufficient cash from Gangtok for personal expenses.