Voter Registration: Where Kenya Added 8 Million Voters in 9 Years

Nairobi alone added 680,000 voters between 2013 and 2022. The register grew by 54%. But who were these new voters, and where did they come from?

When the IEBC closed voter registration for the 2022 election, Kenya had 22,120,458 registered voters. That was up from 19,611,423 in 2017, which was up from 14,388,781 in 2013.

Over nine years, Kenya added 7,731,677 voters to the roll. That is more than the entire population of some African countries. The register grew by 54%. But the growth was wildly uneven across counties, and that unevenness had direct political consequences.

The Biggest Gainers: County by County

Let us look at the counties that added the most voters between 2013 and 2022.

Nairobi was the undisputed registration champion. The capital went from 1,732,288 registered voters in 2013 to 2,251,929 in 2017 to 2,416,551 in 2022. That is an addition of 684,263 voters over nine years — a 39% increase. In a city with constant population growth from rural-urban migration, this was expected but still remarkable in scale.

Kiambu grew from 863,199 (2013) to 1,181,076 (2017) to 1,275,168 (2022), adding 411,969 voters (48% growth). As Nairobi's main satellite county, Kiambu's growth mirrors the expansion of the Nairobi metropolitan area.

Nakuru jumped from 696,594 (2013) to 949,971 (2017) to 1,055,515 (2022), gaining 358,921 voters (52% growth). With its elevation to city status and economic growth, Nakuru attracted young workers who then registered to vote.

Other notable growers:

• Kakamega: 568,151 → 743,929 → 844,709 (+276,558, or 49%)
• Meru: 489,590 → 702,776 → 772,573 (+282,983, or 58%)
• Machakos: 445,421 → 620,363 → 687,691 (+242,270, or 54%)
• Bungoma: 412,018 → 559,866 → 646,612 (+234,594, or 57%)
• Kisumu: 386,606 → 539,593 → 607,496 (+220,890, or 57%)

The National Growth Picture

The national numbers tell a story of rapid expansion:

• 2013: 14,388,781 registered voters (including 2,637 diaspora)
• 2017: 19,611,423 registered voters (including 4,393 diaspora) — +5,222,642 new registrations
• 2022: 22,120,458 registered voters (including 10,443 diaspora) — +2,509,035 new registrations

The biggest jump was between 2013 and 2017, when 5.2 million new voters were added. The 2017-2022 cycle added only 2.5 million. Why the slowdown? Several factors: the IEBC faced funding constraints, voter registration fatigue among young Kenyans, and COVID-19 disrupted the 2021-2022 registration exercises.

The Youth Factor

The bulk of new registrations came from young voters. By 2017, 51% of registered voters were under 35. The 18-24 age group was the fastest growing segment of the register. These were Kenyans born in the 1990s, part of Kenya's demographic bulge, hitting voting age in a wave.

But here is the catch. Many of these young voters registered and then did not show up. Youth turnout was significantly lower than turnout among older voters. As reported by the Daily Nation, polling station data showed that younger voters were less likely to actually cast their ballots, contributing to the national turnout decline.

Where Growth Was Slowest

Not every county saw dramatic growth. Some were already near their registration ceiling:

• Lamu: 52,359 (2013) → 69,793 (2017) → 81,468 (2022) — small county, modest growth
• Isiolo: 54,587 (2013) → 75,355 (2017) → 89,535 (2022) — 64% growth but small numbers
• Samburu: 61,150 (2013) → 82,794 (2017) → 100,052 (2022) — crossed 100K for the first time

North Eastern counties like Garissa, Wajir, and Mandera also saw growth, but from a very low base. Garissa went from 115,236 to 163,350 to 201,513. Mandera grew from 120,923 to 175,650 to 217,034. In these counties, insecurity and cultural barriers to registration, especially for women, kept numbers lower than the population would suggest.

The Diaspora Story

One of the most dramatic growth stories is the diaspora vote. In 2013, only 2,637 Kenyans outside the country were registered to vote. By 2017, that number grew to 4,393. And by 2022, it had reached 10,443 — a fourfold increase from 2013.

The growth came from expanding the number of registration and polling centres abroad. In 2013, there were 6 diaspora centres in 5 East African countries. By 2017, South Africa was added. By 2022, the IEBC expanded to 12 countries, including the United States, United Kingdom, Canada, Germany, and the UAE.

For the full diaspora voting story, read our piece on how diaspora voting grew from 2,637 to 10,443.

What Registration Growth Means for 2027

The IEBC will likely target 25 million registered voters for 2027. But the real challenge is not registration — it is turnout. Kenya has shown it can register voters at impressive scale. The question is whether it can get them to actually vote.

Counties like Nairobi, with 2.4 million registered voters but only 56% turnout in 2022, represent an enormous pool of untapped political power. The party that figures out how to mobilise those 1 million non-voting Nairobians will have a massive advantage.

For more on the turnout challenge, see the great turnout decline. And for the big picture of Kenya's democratic evolution, read four elections, four stories.

Key Takeaways

1. 7.7 million voters added in 9 years — from 14.4M (2013) to 22.1M (2022)
2. Nairobi added 684,263 voters — the most of any county in absolute terms
3. Meru grew 58% — one of the fastest-growing counties by percentage
4. Diaspora: 2,637 → 10,443 — quadrupled as polling centres expanded to 12 countries
5. 2013-2017 added 5.2M, but 2017-2022 only added 2.5M — registration fatigue and COVID slowed growth

Registration is just step one. Votrack tracks voter registration at every level — from national totals down to individual polling stations. See where voters are being added and where your campaign needs to focus. Request a demo for 2027 planning.