Difference between Section 148, 148A and 151 is a critical concept in income-tax reassessment after 01.04.2021. Many taxpayers receive reassessment notices without understanding which provision applies, why it has been issued, and whether the mandatory procedure followed by the Assessing Officer is legally valid.
Understanding the difference is important because procedural defects at any stage can invalidate reassessment proceedings.
Section 148 – Reopening of assessment
Section 148 empowers the Assessing Officer to reopen a completed assessment if income is believed to have escaped assessment.
However, after 01.04.2021, section 148 cannot be invoked directly in most cases. It can be issued only after following the procedure under section 148A.
In simple terms:
- Section 148 is the final reopening notice
- It comes after the preliminary checks under section 148A
Section 148A – Opportunity before reopening
Section 148A was introduced to prevent mechanical and arbitrary reassessments.
It requires the Assessing Officer to:
- Conduct preliminary enquiry (if required)
- Issue a show cause notice under section 148A(b)
- Consider the assessee’s reply
- Pass a speaking order under section 148A(d)
Only if this procedure is properly followed can a notice under section 148 be issued.
This stage is crucial because many reassessment cases fail due to defective 148A procedure.
Section 151 – Approval of higher authority
Section 151 deals with sanction / approval for reopening.
Depending on the time elapsed:
- Approval of specified higher authority is mandatory
- Approval must be prior, reasoned, and valid
Mechanical or blanket approvals under section 151 are a common ground on which reassessments are struck down by courts.
How these three sections work together
In sequence:
- Information suggesting escapement of income
- Notice under section 148A(b)
- Order under section 148A(d)
- Approval under section 151
- Issue of notice under section 148
If any step is missing or defective, the entire reassessment may become invalid.
Where most reassessment notices fail
Common defects include:
- No proper enquiry before issuing 148A(b) notice
- Vague or incomplete allegations
- Non-consideration of assessee’s reply
- Mechanical approval under section 151
- Limitation issues ignored
These are not technicalities—they go to the root of jurisdiction.
Difference Between Section 148, 148A and 151 (Tabular Comparison)
| Section | Role in Reassessment | Mandatory After 01.04.2021 | Common Legal Defects |
|---|---|---|---|
| 148 | Final notice reopening assessment | Yes, after 148A | Issued without valid 148A |
| 148A | Pre-reassessment safeguard | Yes | Vague SCN, no enquiry |
| 151 | Approval of higher authority | Yes | Mechanical sanction |
Why Courts Quash Reassessments Frequently
Courts across India have consistently held that reassessment is a jurisdictional proceeding. If the mandatory procedure under section 148A or approval under section 151 is defective, the entire reassessment collapses.
Common reasons include:
- No proper enquiry before issuing 148A(b)
- Non-consideration of assessee’s reply
- Mechanical approval under section 151
- Limitation ignored
These are not technical lapses but go to the root of jurisdiction.
It is important to note that reassessment provisions after 01.04.2021 are no longer mere procedural formalities. The law now places a heavy jurisdictional burden on the Assessing Officer to strictly adhere to each statutory safeguard. Any casual, hurried, or template-based action defeats the very object of sections 148A and 151.
Courts have repeatedly emphasized that reassessment is not a power to review or re-examine concluded matters at will. It is a conditional power, exercisable only when statutory pre-conditions are fully satisfied. Therefore, understanding the distinction and inter-linkage between sections 148, 148A, and 151 is essential for both taxpayers and professionals defending reassessment proceedings.
Practical Takeaway for Taxpayers
If you have received a reassessment notice:
- Do not assume it is valid
- Check compliance with sections 148A and 151
- A defective notice can be challenged successfully
Related reading
- Received a 148A Notice? What to Do Within 48 Hours
- How to Reply to a 148A(b) Notice – Practical Reply Structure
- Difference Between Section 148, 148A and 151 – Explained Simply
- Can an Assessment Be Reopened Only on Audit Objection?
- Section 148A Reassessment Quashed – Key Case Laws on Defective Procedure
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