Quick Answer: What is the Machakos Postal Code? The main postal code for Machakos is 90100 (Machakos GPO — General Post Office). Machakos County postal codes cover 26 post offices ranging from 90100 to 90177, plus 00204 (Athi River) and 00519 (Mlolongo) for the Mavoko area. To send mail to Machakos Town, use: P.O. Box [Number]-90100, Machakos, Kenya.
Machakos County, officially County Number 016, is located in the former Eastern Province of Kenya, sitting directly east of Nairobi. The county covers an area of approximately 6,208 square kilometres and shares borders with Nairobi City County and Kiambu to the west, Embu to the north, Kitui to the east, Makueni to the south, and Kajiado to the southwest. Machakos Town, the county headquarters, lies about 63 kilometres east of Nairobi along the Nairobi-Mombasa highway corridor.
The county is the ancestral home of the Akamba people (also called the Kamba), one of Kenya’s most populous ethnic communities, known historically for their skill in trade, woodcarving, and long-distance commerce. The name “Machakos” is believed to derive from a Maasai name for a local Kamba chief, and the town was one of the earliest colonial administrative centres established in Kenya, dating back to the late 1800s. This rich history gives Machakos a unique cultural identity that blends traditional Kamba heritage with modern urban development.
The county capital, Machakos Town, is served by the Machakos General Post Office (GPO) with the primary postal code 90100. All post offices in Machakos County fall under postal region prefix 9, which covers Eastern Kenya, alongside neighbouring counties such as Kitui, Makueni, and Embu.
Machakos County – Key Facts
| Detail | Information |
|---|---|
| Official County Name | Machakos County |
| County Number | 016 |
| County Capital | Machakos Town |
| Governor (2022–2027) | Wavinya Ndeti |
| Main Postal Code | 90100 (Machakos GPO) |
| Postal Code Range | 90100 – 90177 (also 00204, 00519 for Mavoko area) |
| Postal Region Prefix | 9 (Eastern Kenya) |
| Area | 6,208 km² |
| Population (2019 Census) | 1,421,932 |
| Population Density | 235 people per km² |
| Annual Population Growth | 2.6% (2009–2019) |
| Constituencies / Sub-Counties | 8 |
| County Assembly Wards | 40 |
| Number of Post Offices | 26 |
| Dominant Ethnic Group | Akamba (Kamba people) |
| Distance from Nairobi | ~63 km east of Nairobi City |
| Bordering Counties | Nairobi, Kiambu, Embu, Kitui, Makueni, Kajiado |
Machakos County Post Offices and Postal Codes
Machakos County is served by 26 post offices operated by Posta Kenya, spread across all 8 sub-counties. The table below provides the full list of every post office in Machakos County, its postal code, the nearest town, and the sub-county it serves. All codes beginning with 9 are in the Eastern Kenya postal region. The codes 00204 and 00519 fall under the Nairobi postal zone because Athi River and Mlolongo are part of the greater Nairobi metropolitan area.
| # | Postal Code | Post Office / Town | Sub-County |
|---|---|---|---|
| 1 | 90100 | Machakos GPO (General Post Office) | Machakos Town |
| 2 | 90101 | Masii | Mwala |
| 3 | 90102 | Mwala | Mwala |
| 4 | 90104 | Mitaboni | Kathiani |
| 5 | 90105 | Kathiani | Kathiani |
| 6 | 90106 | Katangi | Yatta |
| 7 | 90107 | Kaviani | Matungulu |
| 8 | 90108 | Kola | Machakos Town |
| 9 | 90110 | Mbiuni | Mwala |
| 10 | 90111 | Kivunga | Mwala |
| 11 | 90112 | Miu | Mwala |
| 12 | 90113 | Muthetheni | Kangundo |
| 13 | 90115 | Kangundo | Kangundo |
| 14 | 90117 | Mutituni | Machakos Town |
| 15 | 90118 | Ndalani | Yatta |
| 16 | 90119 | Matuu | Yatta |
| 17 | 90121 | Emali | Machakos / Makueni border area |
| 18 | 90123 | Kasikeu | Matungulu |
| 19 | 90124 | Kithimani | Yatta |
| 20 | 90139 | Ekalakala | Masinga |
| 21 | 90141 | Masinga | Masinga |
| 22 | 90144 | Kithyoko | Yatta |
| 23 | 90145 | Daystar University Campus | Athi River / Mavoko |
| 24 | 90177 | Mutituni (Tala) | Matungulu |
| 25 | 00204 | Athi River (Mavoko) | Mavoko (Nairobi postal zone) |
| 26 | 00519 | Mlolongo | Mavoko (Nairobi postal zone) |
Machakos County Constituencies and Their Postal Codes
Machakos County has 8 constituencies, each of which doubles as a sub-county for administrative purposes. The constituencies were established under the 2010 Constitution and are represented in the National Assembly. Each constituency has its own Member of Parliament (MP). The table below shows every constituency, its headquarters, main towns served, and the associated postal codes.
| # | Constituency | Headquarters | Main Towns & Areas | Postal Code(s) |
|---|---|---|---|---|
| 1 | Masinga | Masinga Town | Masinga, Ekalakala, Kivaa, Muthesya | 90141, 90139 |
| 2 | Yatta | Matuu | Matuu, Ndalani, Kithimani, Kithyoko, Katangi | 90119, 90118, 90124, 90144, 90106 |
| 3 | Kangundo | Kangundo Town | Kangundo, Muthetheni | 90115, 90113 |
| 4 | Matungulu | Tala | Tala, Kaviani, Kasikeu, Mutituni | 90177, 90107, 90123 |
| 5 | Kathiani | Kathiani | Kathiani, Mitaboni | 90105, 90104 |
| 6 | Mavoko | Athi River | Athi River, Mlolongo, Kinanie, Katani, Syokimau | 00204, 00519, 90145 |
| 7 | Machakos Town | Machakos Town | Machakos Town, Kola, Mutituni, Mumbuni, Mua | 90100, 90108, 90117 |
| 8 | Mwala | Mwala | Mwala, Masii, Mbiuni, Kivunga, Miu | 90102, 90101, 90110, 90111, 90112 |
Machakos County Sub-Counties
Machakos County’s 8 sub-counties match the 8 constituencies. Each sub-county serves as the administrative unit managed by the county government, while the constituency is the political unit represented by a Member of Parliament. The table below lists each sub-county, the number of wards it contains, and the primary postal codes used in that area.
| # | Sub-County | Headquarters | Number of Wards | Main Postal Code(s) |
|---|---|---|---|---|
| 1 | Masinga Sub-County | Masinga | 5 wards | 90141, 90139 |
| 2 | Yatta Sub-County | Matuu | 5 wards | 90119, 90118, 90124, 90144, 90106 |
| 3 | Kangundo Sub-County | Kangundo | 4 wards | 90115, 90113 |
| 4 | Matungulu Sub-County | Tala | 5 wards | 90177, 90107, 90123 |
| 5 | Kathiani Sub-County | Kathiani | 5 wards | 90105, 90104 |
| 6 | Mavoko Sub-County | Athi River | 5 wards | 00204, 00519, 90145 |
| 7 | Machakos Town Sub-County | Machakos Town | 8 wards | 90100, 90108, 90117 |
| 8 | Mwala Sub-County | Mwala | 5 wards | 90102, 90101, 90110, 90111, 90112 |
All 40 County Assembly Wards in Machakos County
Each of the 40 wards in Machakos County elects one Member of County Assembly (MCA) to the Machakos County Assembly. The wards are the smallest electoral and administrative units in the county. Below is the complete list of all 40 wards grouped by constituency / sub-county.
| # | Ward Name | Constituency |
|---|---|---|
| 1 | Kivaa | Masinga |
| 2 | Masinga Central | Masinga |
| 3 | Ekalakala | Masinga |
| 4 | Muthesya | Masinga |
| 5 | Ndithini | Masinga |
| 6 | Ndalani | Yatta |
| 7 | Matuu | Yatta |
| 8 | Kithimani | Yatta |
| 9 | Ikombe | Yatta |
| 10 | Katangi | Yatta |
| 11 | Kangundo Central | Kangundo |
| 12 | Kangundo North | Kangundo |
| 13 | Kangundo East | Kangundo |
| 14 | Kangundo West | Kangundo |
| 15 | Tala | Matungulu |
| 16 | Matungulu North | Matungulu |
| 17 | Matungulu East | Matungulu |
| 18 | Matungulu West | Matungulu |
| 19 | Kyeleni | Matungulu |
| 20 | Mitaboni | Kathiani |
| 21 | Kathiani Central | Kathiani |
| 22 | Upper Kaewa / Iveti | Kathiani |
| 23 | Kaewa / Kaani | Kathiani |
| 24 | Lower Kaewa | Kathiani |
| 25 | Athi River | Mavoko |
| 26 | Kinanie | Mavoko |
| 27 | Mua / Syokimau | Mavoko |
| 28 | Katani | Mavoko |
| 29 | Mlolongo | Mavoko |
| 30 | Kalama | Machakos Town |
| 31 | Kola | Machakos Town |
| 32 | Machakos Central | Machakos Town |
| 33 | Mua | Machakos Town |
| 34 | Mumbuni North | Machakos Town |
| 35 | Mutitini | Machakos Town |
| 36 | Mutituni | Machakos Town |
| 37 | Muvuti / Kiima-Kimwe | Machakos Town |
| 38 | Mwala | Mwala |
| 39 | Mbiuni | Mwala |
| 40 | Mwania / Nguumo | Mwala |
Frequently Asked Questions
What is the postal code for Machakos Town?
The postal code for Machakos Town is 90100. This is the main General Post Office (GPO) code for the entire county and serves the county headquarters, Machakos School, Machakos University, Machakos County Referral Hospital, and the county government offices. Mail sent to Machakos Town should use the format: P.O. Box [Number]-90100, Machakos, Kenya.
What is the postal code for Athi River (Mavoko)?
Athi River, which is the urban centre of Mavoko Sub-County, uses postal code 00204. This code falls under the Nairobi postal zone (prefix 0) rather than the Eastern Kenya zone (prefix 9), because Athi River is part of the greater Nairobi metropolitan area. The area is known for the Export Processing Zone (EPZ) and its large industrial and residential estates.
What is the postal code for Kangundo?
Kangundo uses postal code 90115. Kangundo is the headquarters of Kangundo Sub-County and constituency, and is one of the main commercial centres in Machakos County. It is also the nearest major town to Tala, which is the Matungulu sub-county headquarters.
What is the postal code for Matuu?
Matuu’s postal code is 90119. Matuu is the headquarters of Yatta Sub-County and sits along the banks of the Tana River, making it an important agricultural and commercial hub in the northern part of Machakos County. Yatta Constituency is one of the largest in the county by area.
What is the postal code for Masinga?
Masinga Town uses postal code 90141. Masinga is the headquarters of Masinga Sub-County in the north of Machakos County. The area is well known for the Masinga Dam, which is Kenya’s largest dam and part of the Seven Forks hydroelectric project on the Tana River. The dam provides a significant portion of Kenya’s electricity.
What is the postal code for Kathiani?
Kathiani uses postal code 90105. Kathiani is the headquarters of Kathiani Sub-County and is a farming community known for horticultural produce including mangoes, which are exported to markets in Nairobi and beyond. Mitaboni, nearby, uses code 90104.
What is the postal code for Mwala?
Mwala Town uses postal code 90102. Mwala is the headquarters of Mwala Sub-County and serves as a commercial centre for the surrounding farming communities. Masii (90101), Mbiuni (90110), Kivunga (90111), and Miu (90112) are all post offices serving different parts of the Mwala sub-county.
What is the postal code for Mlolongo?
Mlolongo uses postal code 00519. Mlolongo is a fast-growing town on the Nairobi-Mombasa highway within Mavoko Sub-County. Like Athi River, it falls under the Nairobi postal zone prefix (0) rather than the Eastern Kenya zone (9), reflecting its geographic and economic integration with the Nairobi metropolitan area.
How many post offices are in Machakos County?
Machakos County has 26 post offices operated by Posta Kenya across all 8 sub-counties. The main GPO is in Machakos Town (90100). The busiest post offices are in Machakos Town, Athi River, Matuu, Kangundo, and Masinga, which serve the most densely populated areas of the county.
What postal region does Machakos County fall under?
Most of Machakos County falls under postal region prefix 9, which covers Eastern Kenya and is administered alongside neighbouring counties like Kitui, Makueni, and Embu. However, the Mavoko sub-county towns of Athi River (00204) and Mlolongo (00519) fall under postal region prefix 0 (Nairobi and Central Kenya) due to their location within the greater Nairobi metropolitan zone.
Does Machakos County have a zip code?
The term “zip code” is specific to the United States Postal Service (USPS). In Kenya, the correct term is postal code. Machakos County’s postal codes are 5-digit numbers such as 90100 (Machakos Town), 00204 (Athi River), and 90119 (Matuu). When filling in international forms online that ask for a “zip code” or “postcode”, use the postal code for your specific Machakos town as listed in the tables above.
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