India sends one of the larger international contingents to the International Space Development Conference (ISDC), and for nearly all of those attendees, the hardest part of the trip has nothing to do with flights or hotels. It is getting a visa appointment on the calendar early enough to matter. ISDC 2027 runs May 27 to 30, and for an attendee applying from India, the visa timeline, not the conference dates, is usually the thing that determines whether the trip happens at all.
Do Indian Citizens Need a Visa to Attend ISDC 2027?
Yes. India is not part of the U.S. Visa Waiver Program, so Indian passport holders cannot travel to ISDC 2027 on an ESTA authorization the way citizens of some other countries can. Attendance at a conference like ISDC generally falls under the B-1 business visitor category, the B-2 tourism category, or a combined B-1/B-2 visa, and getting one requires a full visa application and an in-person interview at a U.S. embassy or consulate. NSS also provides an official invitation letter to support that application. What the letter does, what it does not do, and how to request one are covered in How to Request Your ISDC 2027 Visa Invitation Letter.
How Long Is the Visa Wait From India Right Now?
The wait is longer than almost anywhere else in the world, though the exact number depends entirely on when you check and which consulate you apply through. Estimates published by immigration services and visa-tracking sites in 2026 have ranged from under three months at the fastest Indian posts to well over a year at the slowest, and those estimates shift from month to month as consulates add or lose interview capacity. With visa timelines this volatile, no number printed in this post would still be accurate by the time you read it.
The only figure worth planning around is the one on the U.S. Department of State’s Global Visa Wait Times tool, which the agency updates on a monthly cycle and describes as a maximum estimate rather than a guarantee. The same page notes that appointments are continuously added, so an applicant who books the earliest available slot today may end up being offered an earlier one before the interview date arrives. Checking that tool now, however long it currently shows for India, is the single most useful thing an Indian attendee can do before deciding when to start.
Does It Matter Which Indian Consulate You Apply Through?
It can. The United States operates five visa-issuing posts in India, the Embassy in New Delhi and Consulates General in Mumbai, Chennai, Hyderabad, and Kolkata, and each is assigned a home jurisdiction covering specific Indian states. Applicants are generally expected to apply within their own jurisdiction, but visa timelines at the five posts do not move in sync with each other, and it is common practice for applicants to weigh appointment availability at a post outside their home region if the difference is significant. That is a judgment call best made with current numbers in hand from the official tool rather than a fixed rule, since a consulate can reasonably ask why an applicant outside its usual jurisdiction is applying there.
Can Attending ISDC 2027 Get You an Expedited Appointment?
No, and this is worth knowing before requesting one. The State Department’s own guidance is specific on this point: travel to attend an annual business, academic, or professional conference does not qualify for an expedited interview appointment. Expedite requests are reserved for genuine emergencies, such as a death in the family, a medical crisis, or a documented school start date, and a consular section will only consider one after an applicant has already completed the DS-160 form, paid the visa fee, and booked a regular appointment. An ISDC invitation letter establishes the purpose of a trip for the visa application itself, but it does not change where an applicant lands in the appointment queue.
What Should Indian Attendees Do Right Now to Stay on Schedule for May 2027?
Start the visa process well before ISDC 2027 registration opens. Registration is expected to begin in autumn 2026, but the invitation letter request process is already open, and nothing about the visa timeline requires waiting for registration first. Request the letter, complete the DS-160, pay the fee, and book the earliest available interview slot at whichever post shows the most reasonable wait on the official tool that day.
Where the Conversation Continues: ISDC 2027
None of this is unique to ISDC. It is simply what applying for a U.S. visitor visa from India looks like right now, and it applies equally to any Indian traveler headed to any U.S. conference in 2027. NSS’s own resources for international travelers, linked below, are a reasonable next stop for anyone still sorting out invitation letters or general entry requirements beyond the visa timeline itself.
👉 Learn more for international travelers attending ISDC 2027
Frequently Asked Questions
Can I apply for my visa before I have registered for ISDC 2027?
Yes. Nothing in the visa process requires proof of paid conference registration, and requesting the NSS invitation letter does not require it either. Given how far in advance an Indian applicant may need to book an interview, starting the DS-160 and appointment process before registration opens is generally the better order of operations, not the riskier one.
What happens if my visa interview date falls after ISDC 2027 has already started?
Apply as early as you possibly can, since a visa is generally not tied to your specific travel dates and the process has more than one step. If the earliest interview date available to you falls after the conference begins, you may still have options, including requesting an expedited appointment and checking availability at other consular posts. Be aware that changing a booked appointment can be limited and may carry a cost, so review the current rules before you make any changes. Requirements and procedures change, so please confirm everything directly with the official U.S. Mission India website. This is general information for attendees and not immigration or legal advice.
Do family members traveling together each need their own visa and invitation letter?
Yes. A U.S. visitor visa is issued to an individual, not a household, so each traveling family member who is not a U.S. citizen or otherwise exempt needs their own visa application and interview. NSS’s general invitation letter request form covers any ISDC attendee, including someone attending as an enthusiast rather than a presenter, so a traveling spouse or relative can typically request their own letter the same way, applying separately since the letter and the visa are each issued per person.