Dear aspirants, the IB ACIO notification has been released with 3717 vacancies. This recruitment is conducted to fill Assistant Central Intelligence Officer Grade–II/Executive (ACIO-II/Exe) positions in the General Central Service, Group 'C' (Non-Gazetted, Non-Ministerial). Candidates must clear the Tier 1 (Written examination), Tier 2 (Descriptive paper), and Tier 3 (Interview) stages to become an IB ACIO. Interested candidates should apply on or before 10th August, 2025 (23:59 hrs). There are many books that provide knowledge about the Intelligence Bureau (IB) in the modern world. Among these books, this page highlights the important ones candidates should choose for IB ACIO exam preparation, along with other relevant details. This article covers the details of subject-wise key books for Tier 1, Tier 2, and General Categories. For any queries, kindly visit the FAQs listed below.

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IB ACIO Books 2025 - Tier 1

The number of candidates applying for this prestigious exam continues to grow each year. So, here are the essential and significant books for preparing for the IB ACIO Tier 1 exam, which are crucial for all candidates undertaking this highly competitive test. 

IB ACIO Books 2025 - Tier 2

Many choices exist for preparing for the IB ACIO exam. To help avoid the confusion experienced by candidates under stress, we have gathered the top books for preparation for the IB ACIO Tier 2 Exam. The recommended books below are the recommendations from our experts.

1. Intelligence Bureau ACIO Grade-II/Executive Exam Tier-I & Tier-II PWB - 1991 by Pratiyogita Kiran.

2. IB ACIO: Grade II/Executive (Tier II) Descriptive Exam & Interview Guide - R. Gupta’s.

IB ACIO Books 2025 - General

Candidates to learn about the Intelligence Bureau (IB) can generally consider the following books.

1. IB Intelligence Bureau Security Assistant and Executive (Group C) Exam Books by V. V. K Subburaj.

2. IB ACIO - Grade II (Concise Edition) 2021 Edition - BHI Editorials.

3. Intelligence Bureau Assistant Central Intelligence Officer - GK Publication.

IB ACIO Best Books - Subject Wise

Before going into the list of subject-wise best books, candidates need to know the subjects that are being covered in IB ACIO exam 2025 for Tier 1 and Tier 2. The subjects included in the IB ACIO exam are English, Reasoning / logical Aptitude, General studies, Numerical Aptitude, Current Affairs for Tier 1 exam, whereas Tier 2 is a descriptive paper (Essay, English comprehension, Long answers - on topics such as Current Affairs, Economics, Socio-political issues, etc.) The subject-wise best books are listed below.

IB ACIO Books - English Language

Below are the IB ACIO books for English. Candidates can practice questions from all the topics included in the English section.

IB ACIO Books PDF For English Language

IB ACIO Books - Reasoning / Logical Aptitude

Here are the IB ACIO books focused on Reasoning Ability / Logical Aptitude. Aspirants can work on questions covering all subjects in the Reasoning Ability / Logical Aptitude.

IB ACIO Books PDF For Reasoning Ability

IB ACIO Books - Numerical Aptitude

The Numerical Aptitude is nothing but Quantitative Aptitude. Practice questions from all the topics are included in the quantitative aptitude section provided below.

IB ACIO Books PDF For Numerical Aptitude

IB ACIO Books - Current Affairs

The IB ACIO Book PDF 2025 for the current affairs section is added below for the candidate's reference.

IB ACIO Books PDF For Current Affairs

IB ACIO Books - Descriptive Paper

The descriptive paper mock test page is mentioned below.

IB ACIO Descriptive Paper Online Mock Test Series

FAQs

Q: What are the best books for IB ACIO Tier 1 preparation in 2025?

Top recommended books include:

• B-ACIO Tier-I Guide by R. Gupta’s

• ACIO Exam PWB - 1991 by Pratiyogita Kiran

• Kiran Tier 1 Practice Workbook

• Kiran’s Tier-I Hindi Workbook by Pratiyogita Kiran and KICX.

Q: Which books are useful for the descriptive paper in IB ACIO Tier 2?

For the IB ACIO Tier 2 descriptive paper, candidates can refer to:

• IB ACIO: Grade II/Executive (Tier II) Descriptive Exam & Interview Guide by R. Gupta’s

• Intelligence Bureau ACIO Grade-II/Executive Exam Tier-I & Tier-II PWB - 1991 by Pratiyogita Kiran

Q: Are there any bilingual or Hindi medium books for IB ACIO preparation?

Yes, the Kiran’s Intelligence Bureau (I.B.) Security Assistant/Executive Tier-I Exam Practice Work Book is available in Hindi and is suitable for Hindi medium candidates.

Q: Is there any book that covers both Tier 1 and Tier 2 of the IB ACIO exam?

Yes, the Intelligence Bureau ACIO Grade-II/Executive Exam Tier-I & Tier-II PWB - 1991 by Pratiyogita Kiran covers both tiers.

Q: What general books can help candidates understand the IB and its functioning?

Candidates can refer to the following general books:

• IB Intelligence Bureau Security Assistant and Executive (Group C) Exam Books by V. V. K Subburaj

• IB ACIO - Grade II (Concise Edition) 2021 Edition by BHI Editorials

• Intelligence Bureau Assistant Central Intelligence Officer by GK Publication

Q: Why is it important to use expert-recommended books for IB ACIO preparation?

Using expert-recommended books helps candidates stay focused, practice relevant content, and increase their chances of success through structured preparation.