Skip to content

Guide to the 2023 Review of Parliamentary constituencies

Appendix D

Rules for redistribution of seats (Schedule 2 to the Act)

Number of constituencies

  1. The number of constituencies in the United Kingdom shall be 650.

Electorate per constituency

  1. (1) The electorate of any constituency shall be –

(a) no less than 95% of the United Kingdom electoral quota, and

(b) no more than 105% of that quota.

(2) This rule is subject to rules 4(2), 6(3) and 7.

(3) In this Schedule the “United Kingdom electoral quota” means –

U / 645

where U is the electorate of the United Kingdom minus the electorate of the constituencies mentioned in rule 6.

Allocation of constituencies to parts of the United Kingdom

  1. (1) Each constituency shall be wholly in one of the four parts of the United Kingdom (England, Wales, Scotland and Northern Ireland).

(2) The number of constituencies in each part of the United Kingdom shall be determined in accordance with the allocation method set out in rule 8.

Area of constituencies

  1. (1) A constituency shall not have an area of more than 13,000 square kilometres.(2) A constituency does not have to comply with rule 2(1)(a) if –

(a) it has an area of more than 12,000 square kilometres, and

(b) the Boundary Commission concerned are satisfied that it is not reasonably possible for the constituency to comply with that rule.

Factors

  1. (1) A Boundary Commission may take into account, if and to such extent as they think fit –

(a) special geographical considerations, including in particular the size, shape and accessibility of a constituency;

(b) local government boundaries which exist, or are prospective, on the review date;

(c) boundaries of existing constituencies;

(d) any local ties that would be broken by changes in constituencies;

(e) the inconveniences attendant on such changes.

(1A) In the case of a local government boundary which is prospective on the review date, it is that boundary rather than any existing boundary which it replaces, which may be taken into account under sub-paragraph (1)(b).

(2) The Boundary Commission for England may take into account, if and to such extent as they think fit, boundaries of the English regions specified in sub-paragraph (2A) as they exist on the most recent ordinary council-election day before the review date.

(2A) [Specifies the English regions as per Appendix C above.]

(3) This rule has effect subject to rules 2 and 4.

Protected constituencies

  1. (1) There shall be two constituencies in the Isle of Wight.

(2) There shall continue to be –

(a) a constituency named Orkney and Shetland, comprising the areas of the Orkney Islands Council and the Shetland Islands Council.

(b) a constituency named Na h-Eileanan an Iar, comprising the area of
Comhairle nan Eilean Siar.

(c) a constituency named Ynys Mon, comprising the area of the Isle of
Anglesey County Council.

(3) Rule 2 does not apply to these constituencies.

Northern Ireland

  1. (1) In relation to Northern Ireland, sub-paragraph (2) below applies in place of rule 2 where –

(a) the difference between –

(i) the electorate of Northern Ireland, and

(ii) the United Kingdom electoral quota multiplied by the number of seats in Northern Ireland (determined under rule 8)exceeds one third of the United Kingdom electoral quota, and

(b) the Boundary Commission for Northern Ireland consider that having to apply rule 2 would unreasonably impair –

(i) their ability to take into account the factors set out in rule 5(1), or

(ii) their ability to comply with section 3(2) of this Act.

(2) The electorate of any constituency shall be –

(a) no less than whichever is the lesser of –

N−A

and 95% of the United Kingdom electoral quota, and –

(b) no more than whichever is the greater of –

N+A

and 105% of the United Kingdom electoral quota,
where –

N is the electorate of Northern Ireland divided by the number of seats
in Northern Ireland (determined under rule 8), and A is 5% of the United
Kingdom electoral quota.

The allocation method

  1. (1) The allocation method referred to in rule 3(2) is as follows:

(2) The first constituency shall be allocated to the part of the United Kingdom with the greatest electorate.

(3) The second and subsequent constituencies shall be allocated in the same way, except that the electorate of a part of the United Kingdom to which one or more constituencies have already been allocated is to be divided by –

2C + 1

where C is the number of constituencies already allocated to that part.

(4) Where the figure given by sub-paragraph (3) above is the same for two or
more parts of the United Kingdom, the part to which a constituency is to be
allocated shall be the one with the smaller or smallest actual electorate.

(5) This rule does not apply to the constituencies mentioned in rule 6, and
accordingly –

(a) the electorate of England shall be treated for the purpose of this rule as
reduced by the electorate of the constituencies mentioned in rule 6(1);

(b) the electorate of Scotland shall be treated for the purposes of this rule as
reduced by the electorate of the constituencies mentioned in rule 6(2)(a)
and (b);

(c) the electorate of Wales shall be treated for the purposes of this rule as
reduced by the electorate of the constituency mentioned in rule 6(2)(c).

Interpretation

  1. (1) This rule has effect for the purposes of this Schedule.

(2) Subject to sub-paragraph (2A), the “electorate” of the United Kingdom, or of a part of the United Kingdom or a constituency, is the total number of persons whose names appear on the relevant version of a register of parliamentary electors in respect of addresses in the United Kingdom, or in that part or that constituency.

For this purpose the relevant version of a register is the version that is required by virtue of subsection (1) of section 13 of the Representation of the People Act 1983 to be published no later than the review date, or would be so required but for –

(a) any power under that section to prescribe a later date, or

(b) subsection (1A) of that section.

(2A) In relation to a report under section 3(1) that a Boundary Commission is required (by sections 3(2)) to submit before 1 July 2023, the “electorate” of the United Kingdom, or of a part of the United Kingdom or a constituency, is the total number of persons whose names appear on a register of parliamentary electors (maintained under section 9 of the Representation of the People Act 1983) in respect of addresses in the United Kingdom, or in that part of that constituency, as that register has effect on 2 March 2020.

(3) “Local government boundaries” are –

(a) in England, the boundaries of counties and their electoral divisions,
districts and their wards, London boroughs and their wards and the City of London,

(b) in Wales, the boundaries of counties, county boroughs, electoral divisions, communities and community wards,

(c) in Scotland, the boundaries of local government areas and the electoral wards into which they are divided under section 1 of the Local Governance (Scotland) Act 2004, and

(d) in Northern Ireland, the boundaries of wards.

(3A) A local government boundary is “prospective” on a particular date if, on that date–

(a) it is specified in a provision of primary or secondary legislation, but

(b) that provision is not yet in force for all purposes.

(3B) For that purpose –

(a) “primary legislation” means –

(i) an Act of Parliament

(ii) an Act of the Scottish Parliament

(iii) an Act of Senedd Cymru; or

(iv) Northern Ireland legislation and

(b) “secondary legislation” means an instrument made under primary
legislation.

(4) “Ordinary council-election day” is –

(a) in relation to England and Wales, the ordinary day of election of councillors for local government areas;

(b) in relation to Scotland, the day on which the poll is held at ordinary
elections of councillors for local government areas;

(c) in relation to Northern Ireland, the day of an election for any district council (other than an election to fill a casual vacancy).

(5) The “review date”, in relation to a report under section 3(1) of this Act that a Boundary Commission is required (by section 3(2)) to submit before a particular date:

(a) 1 December 2020 in the case of a report required to be submitted before 1 July 2023, and

(b) in the case of a report required to be submitted before any other particular date, the date which is two years and 10 months before that date.

(For example, 1 December 2028 in the case of a report required to be
submitted before 1 October 2031).

(6) “The United Kingdom electoral quota” has the meaning given by rule 2(3).

(7) A reference in rule 6(2)(a) or (b) to an area is to the area as it existed on the coming into force of Part 2 the Parliamentary Voting System and Constituencies Act 2011, and the reference in rule 6(2)(c) to the area of the Isle of Anglesey County Council is to the area as it existed on the coming into force of the Schedule to the Parliamentary Constituencies Act 2020.

Back to top