Section 522
Section 522: technical defects don't invalidate returns or assessments
Section 522 is a general "substance over form" savings provision - it stops a return of income, an assessment, a notice, or other proceeding from being struck down purely because of a technical mistake, defect or omission, as long as it is, in substance, aligned with what the Act intends.
The general rule
No return of income, assessment, notice, summons or other related proceeding - whether furnished, made, issued, taken, or purported to be - is invalid, or deemed invalid, merely because of a mistake, defect or omission, if it is in substance and effect in conformity with, or according to the intent and purposes of, the Act.
A specific example the section calls out
No assessment is invalid on the ground of a mistake, defect or omission in quoting a computer-generated Document Identification Number, as long as the assessment order is referenced by that number in some manner. This addresses a narrow but real risk in a heavily digitised, DIN-tracked assessment system - a clerical slip in the DIN reference alone doesn't blow up an otherwise-valid assessment.
Frequently asked questions
Can a tax notice be challenged just because of a typo or minor defect?
Not on that basis alone - Section 522 protects a return, assessment, notice or other proceeding from being invalidated merely because of a mistake, defect or omission, as long as it is substantively in conformity with the Act's intent.
Does a wrong Document Identification Number invalidate my assessment?
Not automatically - Section 522(2) specifically protects an assessment from invalidity due to a mistake, defect or omission in quoting the DIN, as long as the order is referenced by that number in some manner.
Want this applied to your actual filing, not just explained?
Get help if you're disputing a notice or assessment on technical groundsLast updated 9 September 2026