Elections and the vote
How electoral boundaries are drawn
The Election Commission's delimitation reviews, the Thirteenth Schedule rules, and why constituency maps change between elections.Direct answer
The Election Commission reviews parliamentary and state constituency boundaries at intervals of not less than eight years, applying principles in the Thirteenth Schedule of the Federal Constitution. Its recommendations take effect after approval by the Dewan Rakyat, while changing the number of seats requires a two-thirds constitutional amendment.
Example from your election context
Worked example
Why a seat's history stops in InfoUndi
When a constituency was redrawn, InfoUndi marks earlier results as boundary-affected instead of pretending continuity. That label is delimitation at work: the seat on today's map is not the same seat that voted under the old boundary.
- Review body
- Election Commission (SPR)
- Minimum interval
- 8 years between reviews
- Approval
- Dewan Rakyat
- Changing seat numbers
- Two-thirds amendment
The delimitation process
Under Article 113 the Election Commission proposes new boundaries, publishes them and holds local inquiries where the state government, local authorities or groups of one hundred or more affected electors may make representations. After any revision, the recommendations are reported through the Prime Minister to the Dewan Rakyat for approval. Because Article 46 fixes the number of parliamentary seats, adding seats is a constitutional amendment needing a two-thirds majority.
- Reviews cannot start less than eight years after the completion of the previous review.
- Affected electors can take part: one hundred or more registered electors in a constituency may object during local inquiries.
- The Dewan Rakyat approves the final recommendations.
- Increasing or reducing the number of seats requires amending the Constitution.
Principles, and why the map changes
The Thirteenth Schedule directs that constituencies within a state ought to be approximately equal in electors, while allowing a measure of weightage for rural areas, and asks the Commission to respect administrative boundaries and local ties. The most recent completed reviews are Peninsular Malaysia in 2018, Sabah in 2019 and Sarawak in 2015, which are the boundary sets shown on InfoUndi's maps.
- Electorate sizes still differ substantially between constituencies; the electorate lens on any election record shows the range.
- When a boundary changes, results before and after are not directly comparable.
- InfoUndi marks redrawn seats as boundary-affected instead of presenting a false continuity.
- State assembly boundaries are reviewed for each state on its own cycle.
Common questions
Why do constituency boundaries change?
Population and registration patterns shift. The Constitution requires periodic reviews, at least eight years apart, so that constituencies within a state remain approximately equal, with allowance for rural weightage.
Who approves new boundaries?
The Dewan Rakyat approves the Election Commission's recommendations. Changing the total number of seats requires a two-thirds constitutional amendment.
Are all constituencies the same size?
No. The Thirteenth Schedule allows rural weightage, and electorate sizes vary widely. InfoUndi's electorate lens shows the largest and smallest electorates in every election record.