India asks for a separate online form on top of any visa or e-visa, with its own deadline. The Bureau of Immigration’s general guidelines page covers that form and the other requirements that sit outside the visa application.
Submit the e-Arrival card within 72 hours
“Foreigner must complete and submit the e-Arrival card online within 72 hours before their arrival in India at https://indianvisaonline.gov.in/earrival or via official Indian Visa Su-Swagatam mobile app.” The card is a separate step from the visa, so add it to your pre-departure checklist.
A visa does not guarantee entry
“Grant of an Indian Visa/Visa Free Regime does not confer the right of entry which is subjected to the discretion of Immigration Authorities.” A valid visa gets you to the immigration counter. The officer there decides the rest.
Clearance on arrival and departure, for everyone
“The Citizens of India as well as foreigners are required to obtain Immigration clearance both at the time of arrival as well as departure to/from India.”
Passport and visa, with exceptions the page does not name
“Foreigners except certain categories who are travelling to India are required to hold a valid passport and valid visa.” The page does not say who the excepted categories are. If you think you qualify, ask the Bureau of Immigration or your visa-issuing post. For visa types, fees and application steps, use the visa-issuing authority’s own pages.
Pakistani nationals
“Pakistani nationals can arrive by Air only at Delhi, Mumbai and Chennai ICPs.” The guidance names no other airport or mode of entry.
Arrival and departure seals
“It is one’s responsibility to make sure that the Arrival/Departure seals get affixed on their passports.” If a seal is missing, the page says: “please get in touch with the nearest FRRO or Immigration Post to make sure the seal gets affixed and enjoy a hassle-free travel.”
Yellow fever
“Persons from Yellow Fever (YF) endemic countries (or if he/she has visited any Yellow Fever (YF) endemic country during past 6 days) will be required to possess a valid certificate of Yellow Fever vaccination from an authorized vaccination centre.”
The rule follows where you have been in the six days before arrival, not your nationality, so a multi-stop itinerary can trigger it. The page does not list which countries count as endemic.
Indian citizens arriving from Nepal by air
“Indians traveling from Nepal by Air are required to carry either a valid Indian passport or Original Indian Voter ID card with photograph issued by the Election Commission of India.”