ISRO scientist recruitment 2026: CBT postponed from 19 Oct to 29 Oct, what changes for 175 posts

Short answer: if you applied for ISRO scientist recruitment 2026 (Scientist/Engineer 'SC', Advt ISRO:ICRB:03(EMC):2026), your written test is not today. ISRO's recruitment page now says the CBT, which was scheduled for Monday, 19 October, "is postponed to 29.10.2026 (Thursday)". ISRO hasn't said why. Your call letter will come to your registered email, there is no download link, and applications haven't reopened.

What exactly changed

Only the date. The remark on ISRO's page for this advertisement reads: "Date of conduct of Computer Based Test (CBT) is postponed to 29.10.2026 (Thursday)", sitting above the older line, "Date of conducting CBT - 19th October, 2026". The careers page carries the same notice. Third-party job sites that checked ISRO's page on 18 October already showed the new date, which is why searches for "isro exam" and "isro exam date 2026" spiked this morning as candidates checked whether the test was on.

Everything else in the 27 August advertisement stands until ISRO issues a corrigendum:

Practical steps this week:

1. Search your inbox and spam for mail from ISRO/ICRB. The advertisement tells candidates to check spam and junk folders regularly. If you received a call letter for 19 October, don't assume its date is valid; wait for a fresh one or follow ISRO's instructions.
2. Rebook travel. ISRO doesn't pay travel allowance for the written test (it reimburses second-class train fare only for the interview), so any cancellation charges are yours.
3. Use the extra ten days on the papers ISRO itself publishes. The recruitment page links previous question papers for Electronics, Mechanical and Computer Science from 2023 and 2025.
4. Write to ISRO only if your question isn't answered in the advertisement or FAQ. The address is rmt-icrb@isro.gov.in; ISRO says it won't reply to queries already covered.

How the CBT is marked, and why 50% is harder than it looks

The test has two parts, and you must clear each one separately:

• Part A, 90 minutes: 80 discipline-specific MCQs worth 80 marks. +1 for a right answer, −1/3 for a wrong one, zero for a blank.
• Part B, 30 minutes: aptitude (numerical, logical, diagrammatic, abstract and deductive reasoning), up to 15 MCQs worth 20 marks, no negative marking.

Unreserved candidates need 50% in each part: 40 of 80 in Part A and 10 of 20 in Part B. PwBD candidates, where posts are reserved, need 40%. The negative marking bites in Part A: 50 right and 30 wrong nets you only 40, exactly the line. In Part B there's no penalty, so leaving questions blank only costs you.

Clearing the CBT gets you onto a shortlist, not a job. ISRO calls five candidates per vacancy (at least 10) to interview, so with 99 Electronics seats, roughly 495 people would be called; with 21 Computer Science seats, about 105. The interview is out of 100: technical knowledge 40, general awareness in your field 20, presentation and communication 20, comprehension 10, and academic achievements 10 (3 for an IIT, IISc, IIST, NIT or NIRF top-20 institute, up to 4 for your CGPA or percentage, 3 for an institute rank of 1 to 3).

The final panel weighs the CBT and interview 50:50, and an unreserved candidate needs 50% in the interview and 60% aggregate. If the aggregate uses that same 50:50 split (the advertisement doesn't spell out the formula separately), a CBT score of 60 means you need at least 60 in the interview too, while a CBT of 75 means the 50-mark interview minimum is enough.

Score check: will you clear the CBT, and what interview score you'd need

The calculator runs in your browser and uses only the rules in ISRO's advertisement for ISRO:ICRB:03(EMC):2026: the Part A/Part B marking, the 50% (or 40%) per-part minimums, the 50:50 final weighting and the interview and aggregate minimums. It can't predict the shortlist cut-off, which depends on how everyone else scores.

Fees: the refund you only get by turning up

Every applicant paid ₹750 as a processing fee. ISRO keeps ₹250 as the application fee and refunds the rest only to candidates who appear in the CBT: ₹500 for most, and the full ₹750 for women, SC/ST, PwBD and ex-servicemen candidates, who are exempt from the application fee. The refund goes to the bank account you gave in the form. If you've lost interest in the job, sitting the test on 29 October is still the only way to get that money back.

What to watch for next

• A fresh call letter by email with the venue and reporting time for 29 October.
• Provisional answer keys on ISRO's website within three working days of the test, with five days to object through the link ISRO provides.
• Any corrigendum on the recruitment page, which is where ISRO says it will post changes to vacancies or dates.

We'll update this page if ISRO changes the date again or publishes the answer key.

Timeline

1. 27 Aug 2026

   Advertisement ISRO:ICRB:03(EMC):2026 published; online registration opens.

2. 16 Sep 2026, 11:55 PM

   Registration and fee payment close.

3. Before 18 Oct 2026

   ISRO's careers page lists the CBT for 19 October 2026.

4. By 18 Oct 2026

   Page updated: CBT postponed to Thursday, 29 October 2026.

5. 29 Oct 2026

   CBT at 37 centres (call letters by email).

6. Within 3 working days of the CBT

   Provisional answer keys on ISRO's website; 5 days for objections.