Second Periodic Review
Boundary Commission for Scotland review of Holyrood constituencies, effective for 2026 election.
Last refreshed: 10 April 2026 · Appears in 1 active topic
Why does the Scottish boundary review matter for the 2026 Holyrood election?
Latest on Second Periodic Review
- When were Scottish Parliament constituency boundaries last changed?
- The Second Periodic Review approved in October 2025 is the first revision since 2011, a 15-year gap.
- How does the new Scottish boundary review affect the 2026 Holyrood election?
- Every Holyrood seat is contested under new constituency maps for the first time since 2011, combined with 39 MSPs retiring.
Background
The Second Periodic Review of Scottish Parliament boundaries was conducted by the Boundary Commission for Scotland and approved by the Scottish Parliament in October 2025. It is the first revision of Holyrood constituency and regional boundaries since the boundaries set for the 2011 Scottish Parliament election — a fifteen-year gap between redraws.
The review takes effect for the 7 May 2026 Scottish Parliament election, meaning every Holyrood seat is being contested under a new constituency map. Combined with a record 39 MSPs retiring , the incumbency baseline for 2026 is more disrupted than any Holyrood election since the first in 1999. Electoral Calculus's 7 April 2026 MRP (which projected the SNP on 67 seats, two above the 65-seat majority threshold) incorporates the new boundaries into its seat-level model.
The practical effect of the Second Periodic Review is that no 2026 Holyrood candidate can rely on incumbency advantage in its traditional form: their previous vote share was won in a constituency that no longer legally exists. For Opposition parties, new boundaries mean fresh opportunities in redrawn seats where no sitting MSP can claim a personal vote; for the SNP, they add uncertainty to a majority projection that already sits just two seats above the threshold.