How to apply for IISER IAT: 2026 portal steps, fee and documents
IAT application is the first step in a longer admission path. In the 2026 cycle, candidates registered on the official IISER Admissions portal, completed one examination application, paid a category-based application fee and later sat a computer-based test. IISER programme preferences were submitted only after the result through a separate counselling registration. Applicants to the five partner institutions listed by the 2026 brochure also had to make a second, institution-specific application. These are details of the completed 2026 cycle, not an announcement of a 2027 form or deadline.
Before opening the application form
Start by deciding which degree routes you may want to keep open. The seven IISERs offered several science pathways in 2026, including the five-year BS-MS, while named programmes at Bhopal, Kolkata and Tirupati added B.Tech, computational/data science or economics options. Some required Class XII Mathematics even though the general IAT eligibility rule required only three subjects among Biology, Chemistry, Mathematics and Physics. If you are considering a partner programme at IISc, IIT Madras, IIT Guwahati, IACS or IIEST, note its separate portal and selection instructions before you apply to IAT.
Next, check the IAT 2026 eligibility page against your own record: nationality/category, Class XII passing or appearing year, science subjects, aggregate across all qualifying-examination subjects, and any additional course-specific subject condition. Candidates still waiting for board results could apply in 2026, but admission depended on meeting the final criteria. If you were claiming a reservation or special category, prepare the certificate exactly as required for that cycle. A document uploaded under the wrong category or issued outside its valid period can affect more than the form’s appearance; category may also be used in later seat allocation.
Use only the official portal linked from IISER Admissions. The IAT brochure advised candidates to use their own or parent/guardian contact details because communications would go to the registered email and phone. Before starting, have your personal details and qualifying-examination information ready, and use the current official instructions for image, signature, certificate and file-format requirements. Those operational specifications can change, so do not reuse a remembered file-size rule from a prior year.
Complete one central IAT application
The central application had three important jobs: identify the candidate, establish the qualifying-examination record and register for the test. In 2026, an applicant selected the appropriate Class XII status/year, entered academic information, supplied required documents and confirmed the application. Review spelling and identifying details against official records before final submission, especially the name, date of birth, category, phone number, email and passing-year entry. The application contact information mattered because hall-ticket and admission communication depended on the registered channels.
The 2026 portal opened on 5 March and closed on 13 April at 11:55 pm IST. The published correction window was 16 April at 11 am through 18 April at 11:55 pm. A correction window is not a substitute for checking the form before submitting: it permits only the edits the portal exposes, and the exact allowed fields are cycle-specific. The schedule later listed hall tickets on 24 May for the 7 June examination. These dates have elapsed; they are included to explain the workflow and must not be copied into a future planner.
Before paying, verify that the form is complete and that the category selected matches the supporting evidence. The 2026 application fee was non-refundable. It was ₹2,000 for General/EWS/OBC/OBC-NCL groups, ₹1,000 for SC/ST/PwD and eligible Kashmiri-category groups, and ₹12,000 for foreign nationals. The brochure and fee page should control category edge cases; do not infer the fee from a broad “reserved” label. Save the successful payment acknowledgement and submitted-form confirmation where available.
Application fee is not the Seat Acceptance Fee
There are two distinct payments. The application fee was paid to register for the examination and was non-refundable. A Seat Acceptance Fee (SAF) came later, only after a candidate received an IISER admission offer. In the 2026 fee schedule, SAF was ₹35,000 for General/EWS/OBC/OBC-NCL/PwD/KM categories, including a ₹10,000 non-refundable administrative component, and ₹17,500 for SC/ST categories, including ₹5,000 non-refundable administration. The SAF was adjusted against the first-semester fee after the candidate registered at the allotted IISER; it was not the institute’s complete semester fee, and semester charges differed among IISERs.
Do not pay a later amount just because it appears in an old fee screenshot. For an offer, read the exact round’s payment window and withdrawal rules in the current portal. Missing a SAF deadline could end consideration in later rounds. The fee page also distinguished withdrawal before and after round-wise and final deadlines, with different refund consequences. Keep the fee receipt and note the exact offer round, date and category used.
Separate application routes beyond IISER counselling
The 2026 brochure listed five non-IISER institutions using IAT for specified programmes: IISc Bengaluru BS (Research), IIT Madras BS, IIT Guwahati BS Biomedical Science and Engineering, IACS Kolkata integrated BS-MS, and IIEST Shibpur BS-MS programmes in Chemistry, Physics and Applied Geology. For these routes, IAT registration was only one part of applying. The brochure directed candidates to complete both the IAT application and a separate application on the relevant institution’s programme page. It also warned that partner eligibility could differ from IISER’s criteria.
Keep a small tracker for each target programme: the IAT registration confirmation, the separate institution application number, each institution’s deadline, whether an IAT rank-update step is required, and the institution’s offer-response date. Do not assume that selecting an IISER preference also applies to IISc or another partner. Conversely, do not assume the partner institution uses the IISER common counselling or SAF process; follow its own official notice.
After submission: test, result and preference form
Once registered, follow the official portal for the hall ticket, centre instructions, exam-day requirements, answer-key and response windows. The 2026 exam was held on 7 June from 9 am to noon IST. The provisional answer key appeared on the same day; the candidate-response and objection portal opened on 9 June and closed on 13 June. Final answer key and result were listed for 29 June. After that, the IISER academic-programme preference window ran 2–9 July, closing at 5 pm IST. This preference form was a later counselling step, not a field in the initial exam application.
For any future cycle, check a newly dated brochure before acting. Confirm the portal URL, passing-year eligibility, fee, category documents, allowed correction fields, test date, result process and whether partner applications are needed. The reliable next action is to bookmark the official IISER Admissions portal and each external programme page you intend to apply to, then use the new cycle’s notice as your checklist.