President Uhuru Kenyatta and former Prime Minister Raila Odinga with the BBI documents.

| File photo

Kenya’s 15 new constituencies each year

The push to create 70 more constituencies will see the number of additional electoral units in the past decade rise to 150 -- on average, 15 a year. 

If implemented, this period (2010-2021) will account for creating nearly twice as many constituencies as those created since independence.

93 additional units

In 1963, the country had 117 constituencies, which had risen to 210 by the time of the last review in 2010. This translates to 93 additional units in 47 years.

The Building Bridges Initiative’s Bill to amend the Constitution proposes an extra 70 constituencies, which will require approval by voters in the referendum planned for June.

This will raise the minimum number of constituencies from the current 290, established in 2010 when the Constitution was ratified, to 360. 

In addition, the Senate is proposed to have 94 elected senators -- two representatives of either gender for each of the 47 counties.

These proposed changes alone increase the number of elected lawmakers for both Houses of Parliament from the current 384 to 454.

The number of constituencies has been reviewed upwards four times since independence, leading to an extra 41 electoral units in the first review, 30 in the second, 22 in the third and 80 additional constituencies created in the last addition in 2010.

The demarcation of electoral units in Kenya started with the creation of 117 constituencies in 1963.

Constituency reviews followed in 1966 and 1986, culminating in the creation of 210 constituencies in 1996.

The old constitution had fixed the number of constituencies at a minimum of 188 and a maximum of 210.

Between 1964 and 1966, constitutional amendments led to the abolition of the seven regions of Kenya and the Senate.

By 1966, the House of Representatives that had been renamed the National Assembly had 158 parliamentary constituencies.

These included the original 117 plus 41 newly created constituencies after the Senate was abolished.

In 1986, Parliament fixed the number of constituencies at 188.

The Electoral Commission of Kenya published the names and boundaries of these constituencies in the Gazette. 

It is following the boundary review of 1996 that the ECK increased the number of constituencies from the minimum of 188 to the maximum of 210.

The ECK distributed the 22 additional constituencies in proportion to the population of each province.

Following the ratification of the constitution in 2010 following campaigns by the Grand Coalition Government led by President Mwai Kibaki and Prime Minister Raila Odinga, the Interim Independence Boundaries Review Commission (IIBRC) set out on another review.

“From the public hearings, a majority of the residents wanted their constituencies split, with only a few exceptions such as Taveta, Garsen, Nyeri Town, Mathioya, Kigumo, Likoni, Aldai, Samburu East, Mogotio, Eldama Ravine, Budalang’i, Sabatia, Bonchari, Nyaribari Masaba, West Mugirango, Nyaribari Chache, Rongai and Chepalungu constituencies,” the IIBRC report stated.

With a population of 38,610,097 in 2009, for 290 constituencies, the IIBRC led by Mr Andrew Ligale, used the population quota of 133,138. The quota is broadly arrived at by dividing the country’s population by the number of constituencies.

This is how the regions shared out the additional 80 constituencies in 2010.

With 27 extra constituencies, Rift Valley got the lion’s share, raising its total constituencies to 76.

Nyanza got an additional 10 for its constituencies to reach 42.

Nairobi and Western were the next big beneficiaries, with an extra nine each, increasing their tally to 17 and 33, respectively.

Eastern secured an extra eight constituencies, raising the region’s tally to 44 and North Eastern, with seven more units has 18.

Coast and Central got the least number of additional constituencies -- five each, increasing their total units to 26 and 34, respectively.

Under BBI, Rift Valley counties, earmarked to have 23 extra constituencies, are set to secure the lion’s share of the additional 70 constituencies. 

Nairobi is tipped to have the second highest additional units – 12 -- and Coast counties follow with 10 extra constituencies.

Counties in Central are proposed to have an extra eight constituencies, those in Eastern (7), Western (5), Nyanza (4) and Mandera is the only county in North Eastern recommended to benefit from an extra unit.

Initially, the 70 extra National Assembly seats were to be filled through party lists but the Bill now proposes creation of new constituencies.

The distribution of the seats was also revised to gift four Rift Valley counties -- West Pokot, Nandi, Bomet and Uasin Gishu -- an additional four constituencies. Kwale was the other beneficiary of an extra seat in the revised BBI report, which, however, reduced Nairobi’s share from 16 to 12.

The BBI Bill states that the allocation of additional constituencies among the counties shall prioritise the constituencies underrepresented in the National Assembly on the basis of population quota.

Additionally, the Bill requires the distribution be made in a manner that ensures the number of inhabitants in a constituency is as nearly as possible to the population quota.

Given the country’s population, based on last year’s census, is 47,564,296, the population quota that will inform the distribution of the new constituencies will be 132,123.

BBI also extends the protection of 27 constituencies that did not meet the population quota set by IIBRC in 2010 but which were allowed to continue existing. 

“The creation of additional constituencies shall not result in the loss of a constituency existing before the commencement date of this Act. For greater certainty, any protected constituency in the counties of Tana River, Lamu, Taita Taveta, Marsabit, Isiolo, Nyandarua, Nyeri, Samburu, Elgeyo/Marakwet, Baringo, Vihiga and Busia shall not have their protected status impaired by the delimitation of additional constituencies mentioned in this schedule,” the BBI Bill states.

The BBI report doesn’t indicate the cost of the additional parliamentary seats but an analysis by the Institute of Economic Affairs suggests voters will determine the burden taxpayers will shoulder.

It will cost taxpayers an extra Sh3.7 billion a year to pay for the proposed additional seats, assuming that Kenyans do not elect women in the proposed 360 constituency seats, necessitating the nomination of 180 women to the National Assembly to meet the constitutional requirement that one gender does not dominate more than two-thirds of the elective and appointed seats.

In this worst case-scenario, the institute predicts, Kenyans will have to spend Sh308 million a month on the additional MPs, including the proposed addition of 47 seats in the Senate.

Even in the best case scenario where as many women as are needed to achieve the two-thirds gender rule are elected, taxpayers will still have to fork out an extra Sh726 million a year — Sh60.5 million a month — on the additional MP seats.

The IEA estimated for every additional MP that the BBI proposes in both Houses, it will cost taxpayers at least Sh1.37million a month.

How BBI proposes counties share 70 new constituencies

  • Mombasa   3
  • Kwale  3
  • Kilifi  4
  • Mandera   1
  • Meru  2
  • Embu  1
  • Machakos   3
  • Makueni  1
  • Kirinyaga   1
  • Murang’a    1
  • Kiambu  6
  • Turkana 1
  • West Pokot   1
  • Trans Nzoia  2
  • Uasin Gishu    3
  • Nandi  1
  • Laikipia  1
  • Nakuru    5
  • Narok 3
  • Kajiado   3
  • Kericho   1
  • Bomet  2
  • Kakamega 2
  • Bungoma   3
  • Siaya  1
  • Kisumu   2
  • Nyamira 1
  • Nairobi   12

History of constituency boundary review 


Population (millions

Number of Constituencies

Population quoata





















* 2019




*Refers to the latest census results that could inform BBI boundary review