The Constitution of India
Article 330
Reservation of seats for Scheduled Castes and Scheduled Tribes in the House of the People
(1) Seats shall be reserved in the House of the People for —
(a) the Scheduled Castes;
(b) the Scheduled Tribes except the Scheduled Tribes in the autonomous districts of Assam; and
(c) the Scheduled Tribes in the autonomous districts of Assam.
(2) The number of seats reserved in any State or Union territory for the Scheduled Castes or the Scheduled Tribes under clause (1) shall bear, as nearly as may be, the same proportion to the total number of seats allotted to that State 2 [or Union territory] in the House of the People as the population of the Scheduled Castes in the State or Union territory or of the Scheduled Tribes in the State or Union territory or part of the State or Union territory, as the case may be, in respect of which seats are so reserved, bears to the total population of the State or Union territory.
(3) Notwithstanding anything contained in clause (2), the number of seats reserved in the House of the People for the Scheduled Tribes in the autonomous districts of Assam shall bear to the total number of seats allotted to that State a proportion not less than the population of the Scheduled Tribes in the said autonomous districts bears to the total population of the State.
Explanation —In this article and in article 332, the expression “population” means the population as ascertained at the last preceding census of which the relevant figures have been published:
Provided that the reference in this Explanation to the last preceding census of which the relevant figures have been published shall, until the relevant figures for the first census taken after the year 2026 have been published, be construed as a reference to the 2001 census.
Why this exists
India's Constitution-makers wanted to ensure that historically marginalized communities — Scheduled Castes and Scheduled Tribes — had guaranteed representation in Parliament, since without reservation their numbers might not translate into elected seats under a general electoral system. Assam's autonomous tribal districts were given distinct treatment because of their unique administrative status under the Sixth Schedule and to protect smaller, geographically concentrated tribal populations from being outvoted or overlooked. The freeze on using 2001 census figures (extended by amendment) was meant to prevent states that controlled population growth from losing parliamentary seats relative to those that didn't, until a broader national consensus on delimitation is reached after 2026.
How courts read it
Courts have generally treated the mechanics of seat reservation and delimitation under Article 330 as intertwined with Article 82 and the Delimitation Acts, largely deferring to Parliament and the Delimitation Commission on how exactly proportions are calculated, while affirming that the reservation itself is mandatory, not discretionary. There is no single landmark case that reshaped the Article's core meaning; most litigation around SC/ST reservation in legislatures has centered on Articles 332 and 243D (state assemblies and panchayats) rather than directly on Article 330.
Common misconceptions
- Myth: Only SC or ST candidates can vote in a 'reserved' constituency.
Fact: All voters in that constituency vote as usual; the reservation only limits who can contest as a candidate, not who can vote. - Myth: Reserved seats are fixed forever and never change.
Fact: The specific constituencies reserved can change over time through delimitation exercises, based on updated population data (subject to the current freeze until after the 2026 post-census delimitation). - Myth: The 2001 census freeze means population growth after 2001 is ignored forever.
Fact: The freeze is temporary — it applies only until figures from the first census after 2026 are published, after which recalculation is expected.