Nairobi, Kiambu, Nakuru and Mombasa have emerged as Kenya's strongest economic performers in a new report, while Wajir, Mandera, and Turkana continue to lag due to persistent poverty, weak infrastructure and limited private sector activity.
The 2026 County Development Index (CDI) report shows that Nairobi City County scored 0.96, the highest economic performance score nationally, supported by its contribution of 27.5 per cent of Kenya's Gross Domestic Product (GDP) and a Gross County Product estimated at more than Sh4.1 trillion.
Nairobi hosts the country's biggest concentration of financial institutions, industries, professional services and formal enterprises.
Kiambu County Governor Kimani Wamatangi.
Photo credit: Bonface Bogita | Nation Media Group
Kiambu followed with a score of 0.89 (Sh819.8 billion), Nakuru 0.87 (Sh771.8 billion) and Mombasa 0.84 (Sh711 billion), underscoring the dominance of the Nairobi Metropolitan region in Kenya's economy. Nyeri ranked fifth with 0.81 (Sh265 billion).
The report says Kiambu and Nakuru benefited from their proximity to Nairobi, a strong manufacturing base, robust commercial sectors and high levels of private investment.
Nakuru Governor Susan Kihika
Photo credit: File | Nation Media Group
Mombasa's position was bolstered by its strategic role as Kenya's main port city and its diversified economy, where manufacturing and services account for about 75 per cent of economic output.
The 2026 CDI Report ranks counties using an Economic Performance and Livelihoods Index that goes beyond measuring the size of county economies. It combines eight indicators of Gross County Product, contribution to national GDP, labour force participation, youth unemployment, economic diversification, poverty levels, multidimensional poverty and the business environment.
The Gross County Product provides the most comprehensive measure of the size of a county’s economy by capturing the value of goods and services produced within each county.
The indicators were normalised and weighted to produce scores ranging from zero to one, with higher scores indicating stronger economic performance.
Under the methodology, Gross County Product carried the highest weight of 20 per cent, followed by labour force participation, youth unemployment and headcount poverty at 15 per cent each. Contribution to national GDP, manufacturing and services share, and multidimensional poverty each accounted for 10 per cent, while the business environment contributed 5 per cent.
Murang'a Governor Irung’u Kang’ata.
Photo credit: Dennis Onsongo | Nation Media Group
Other top-performing counties included Meru 0.77 (Sh525billion), Machakos 0.76 (Sh476 billion), Murang'a (0.76), Uasin Gishu 0.76 (Sh296 billion), Kirinyaga (0.74) and Nandi (0.74).
These counties scored highly due to diversified economic activities, lower poverty levels, strong labour force participation and favourable business environments.
“These top counties benefit from relatively diversified economic structures supported by manufacturing, commercial agriculture, logistics, wholesale and retail trade, education, tourism and professional services,” the report released in Nairobi on Tuesday states.
In contrast, the report paints a grim picture for several northern and arid counties which continue to struggle with poverty, weak infrastructure, high unemployment and limited private-sector investment.
At the bottom of the rankings are predominantly Arid and Semi-Arid Lands (ASAL) counties. Wajir posted the lowest CDI score nationally at 0.07 (Sh69.6 billion), followed by Mandera 0.09 (Sh88.4 billion), Turkana (0.12), Samburu 0.15 (Sh36.8 billion), Marsabit (0.16), Garissa 0.18 (Sh76.4 billion), Tana River (0.20), Isiolo 0.22 (Sh46.2 billion) and West Pokot 0.25 (Sh87.1 billion)/
According to the report, these counties continue to be held back by low economic diversification, weak business ecosystems, high unemployment and widespread multidimensional poverty.
“Their low output reflects relatively small populations, limited industrial activity, low investment levels, dependence on livestock production and weak private sector development. These figures demonstrate the highly uneven spatial distribution of economic activity across Kenya and underscore the importance of strengthening regional economic development to reduce concentration within a few counties,” the report said.
The study was conducted by the SDG Kenya Forum and supported by the Gates Foundation. It provides a comprehensive and evidence-based assessment of development performance across Kenya’s 47 counties.
It shows that economic performance is a fundamental determinant of county development, influencing employment creation, household incomes, poverty reduction, fiscal capacity and the overall quality of life.
Counties with diversified economies, productive labour markets, competitive business environments and lower poverty levels are generally better positioned to sustain inclusive economic growth and improve social welfare.
According to the Kenya National Bureau of Statistics (KNBS) Gross County Product Report of 2025, Nairobi City County remains the country’s undisputed economic engine.
The large variation in Gross County Product highlighted the need for counties to pursue economic diversification, industrialisation and value addition to expand local production and increase household incomes.
The report recommends that counties develop county-specific economic diversification strategies based on local comparative advantages and that they also strengthen agricultural value chains, agro-processing and local manufacturing in productive rural counties.
“Counties with diversified economies and stronger infrastructure perform better, while many ASAL counties face high poverty, limited economic diversification and weak labour-market opportunities. They should strengthen county investment promotion and business-enabling systems to attract private sector investment,” it said.
According to economist Samuel Kimote, the top leading counties are enjoying the advantage of good infrastructure, which contributes to good economic performance.
“The strongest-performing counties benefit from a cumulative combination of economic opportunities, infrastructure, human capital, institutional capacity and better service-delivery systems. Conversely, counties facing disadvantages in one dimension frequently face disadvantages in several others. This creates a cycle in which weak infrastructure limits economic activity, weak economic activity constrains own-source revenue, limited fiscal space restricts investment in human capital and services, and weak institutional capacity reduces the effectiveness of available resources,” he said.
On the fiscal management performance across counties, Narok County was listed as the strongest performer with a CDI score of 0.79, owing to exceptional own-source revenue mobilisation (Sh4, 800 per capita), high budget execution (95.5 per cent), moderate wage bill burden (23.3 per cent) and strong financial accountability.
Mombasa County came second (0.69), followed by Nyeri (0.68), Kirinyaga (0.67), Lamu (0.67), Nandi (0.63), Turkana (0.61), Embu (0.60) and Garissa (0.60), which also ranked among the top-performing counties.
A second tier of counties including Siaya, Nakuru, Tana River, Uasin Gishu, Laikipia, Kilifi, Murang’a, Homa Bay, Tharaka-Nithi, Trans Nzoia, Samburu, Meru, Kitui, Elgeyo-Marakwet, Kiambu, Migori, Makueni, Bomet, Baringo, Kericho, Taita-Taveta, Busia, Isiolo, Kwale, Kakamega, Marsabit, Kisumu and Nairobi recorded moderate performance.
Nyamira, with an index of 0.16, recorded the weakest fiscal management performance nationally. The report attributed Nyamira’s poor performance to the highest wage bill burdens (53.9 per cent), weak budget execution (53.8 per cent) and limited own source revenue generation.
Other low-performing counties include Kisii (0.22), Kajiado (0.28), Mandera (0.30), Bungoma (0.33), Machakos (0.33) and Nyandarua (0.33).
