Kiambu Postal Codes – Official Post Offices & Areas

Quick Answer: Kiambu County Main Postal code is 00900 for Kiambu Town. However, the county uses 20+ different postal codes across its 12 sub-counties, including: Thika (01000), Ruiru (00232), Juja (01001), Kikuyu (00902), Limuru (00217), Githunguri (00216), Gatundu (01030), Lari (00220), and others. Each town has its designated postal code for accurate mail delivery.

Kiambu County is one of the most populous counties in Kenya, and it is located just north of Nairobi with over 2.4 million residents. As per the 2010 Kenyan Constitution, Kiambu is designated as County number 022 in Kenya out of the 47 Counties. The county is mainly known as a major residential and industrial centre, with towns like Thika, Ruiru, and Kikuyu facilitating all these.

What Are Kiambu Postal Codes?

Kiambu Postal Code is 00900. It uses the postal region prefix 00, which identifies it as part of the Central region managed by Posta Kenya. This is the same prefix used by Nairobi, as both counties are in the central region. This differs from Nakuru’s 20 prefix, Mombasa’s 80 prefix, or Kisumu’s 40 prefix. The format follows Kenya’s postal code standard five-digit structure: the first two digits (00) represent the broader Central region, while the final three digits pinpoint the specific post office or delivery zone.

For example, 00900 breaks down as:

• 00 = Central region (Kiambu/Nairobi)
• 900 = Kiambu Town (Main Post Office)

All 12 Kiambu Sub-Counties and Their Postal Codes

Kiambu County is divided into 12 sub-counties for administrative purposes, and each has its own postal codes vital for the sorting and delivery of mail on time:

No.	Sub-County	Main Town(s)	Main Postal Code(s)	Population (Approx)
1	Kiambu	Kiambu Town, Githiga, Ikinu	00900, 00903, 00904	200,000+
2	Thika East & West	Thika Town, Madaraka, Ndithini	01000, 01002, 01016	350,000+
3	Ruiru	Ruiru Town	00232	400,000+
4	Juja	Juja, Kalimoni, JKUAT	01001	250,000+
5	Kikuyu	Kikuyu Town, Kerwa	00902, 00906	280,000+
6	Limuru	Limuru Town, Nderu	00217, 00229	180,000+
7	Githunguri	Githunguri Town, Gathiruini, Gathugu	00216, 00239, 00240	170,000+
8	Gatundu North & South	Gatundu, Gatukuyu, Kamwangi, Gituamba, Kanjuku	01030, 01028, 01009, 01003, 01004	160,000+
9	Lari	Kijabe, Matathia, Uplands, Kagwe	00220, 00221, 00222, 00223	120,000+
10	Kiambaa	Karuri	00902 (shared with Kikuyu)	200,000+
11	Kabete	Kabete	00625	160,000+
12	Multiple towns	Various locations	20+ codes total	2.4 Million Total

Kiambu Sub-County – (00900, 00903, 00904)

Kiambu Town is the county’s namesake and administrative center. The main post office (00900) handles most official correspondence for the area.

The main Kiambu Postal Codes are:

• 00900 – Kiambu Town GPO (General Post Office)
• 00903 – Githiga Post Office
• 00904 – Ikinu Post Office

Thika Sub-County – (01000, 01002, 01016)

Thika is an industrial town and a commerce hub in Kiambu County. It lies in the highland region just northeast of Nairobi and serves as the county headquarters. Thika has multiple post offices serving its large population.

The primary Thika Postal Codes are:

• 01000 – Thika Town GPO (General Post Office)
• 01002 – Madaraka Post Office
• 01016 – Ndithini Post Office

Ruiru Sub-County – (00232)

Ruiru is an industrial town and dormitory area for Nairobi, with over half the population working in the capital. The main Ruiru Post Office has the 00232 as its postal code.

Juja Sub-County – (01001)

Juja Town is home to Jomo Kenyatta University of Agriculture and Technology (JKUAT). It is served primarily by the Kalimoni Post Office with the postal code of 01001.

Kikuyu Sub-County – (00902, 00906)

Kikuyu Town is located about 20 km northwest of Nairobi and is one of the oldest towns in Kiambu County with rich missionary history.

The main Kikuyu Postal Codes are:

• 00902 – Kikuyu Post Office
• 00906 – Kerwa Post Office

Limuru Sub-County – (00217, 00229)

Limuru is located on the eastern edge of the Great Rift Valley, about 30 kilometers northwest of Nairobi. It’s mainly known for tea and coffee production.

The key Limuru Postal Codes are:

• 00217 – Limuru Post Office
• 00229 – Nderu Post Office

Githunguri Sub-County – (00216, 00239, 00240)

Githunguri is an agricultural town home to Fresha, one of East Africa’s largest dairy processing plants. Its main Postal codes are as follows:

• 00216 – Githunguri Post Office
• 00239 – Gathiruini Post Office
• 00240 – Gathugu Post Office

Gatundu Sub-County – (01030, 01028, 01009, 01003, 01004)

Gatundu is famous as the hometown of Kenya’s first president, Jomo Kenyatta. The area is divided into Gatundu North and Gatundu South sub-counties.

Gatundu Postal Codes include:

• 01030 – Gatundu Post Office
• 01028 – Gatukuyu Post Office
• 01009 – Kamwangi/Makwa Post Office
• 01003 – Gituamba Post Office
• 01004 – Kanjuku Post Office

Lari Sub-County – (00220, 00221, 00222, 00223)

Lari is located forty kilometers from Nairobi along the Nairobi-Nakuru highway in the western part of Kiambu County, on the edge of the Rift Valley.

The Main Lari Postal Codes are:

• 00220 – Kijabe Post Office
• 00221 – Matathia Post Office
• 00222 – Uplands Post Office
• 00223 – Kagwe Post Office

Kiambaa & Kabete Sub-Counties – (00902, 00625)

Kiambaa is a rapidly growing residential area, sharing postal facilities with Kikuyu. Kabete is home to numerous research institutions and educational facilities.

• 00902 – Karuri/Kiambaa Post Office (shared with Kikuyu)
• 00625 – Kabete Post Office

Complete List of Kiambu Post Offices

Posta Kenya operates numerous post offices throughout Kiambu County, each serving specific geographic areas and communities:

Post Office Name	Postal Code	Sub-County	Town/Location	Services Available
Kiambu GPO	00900	Kiambu	Kiambu Town	Full Services, P.O. Boxes, EMS, Parcels
Githiga	00903	Kiambu	Githiga	P.O. Boxes, Mail Services
Ikinu	00904	Kiambu	Ikinu	P.O. Boxes, Mail Services
Thika GPO	01000	Thika	Thika Town	Full Services, P.O. Boxes, EMS, Parcels, Banking
Madaraka	01002	Thika	Madaraka Estate	P.O. Boxes, Mail Services
Ndithini	01016	Thika	Ndithini	P.O. Boxes, Mail Services
Ruiru	00232	Ruiru	Ruiru Town	Full Services, P.O. Boxes, EMS, Parcels
Kalimoni/Juja	01001	Juja	Juja, JKUAT Area	Full Services, P.O. Boxes, Student Services
Kikuyu	00902	Kikuyu/Kiambaa	Kikuyu Town, Karuri	Full Services, P.O. Boxes, EMS
Kerwa	00906	Kikuyu	Kerwa	P.O. Boxes, Mail Services
Limuru	00217	Limuru	Limuru Town	Full Services, P.O. Boxes, EMS
Nderu	00229	Limuru	Nderu	P.O. Boxes, Mail Services
Githunguri	00216	Githunguri	Githunguri Town	Full Services, P.O. Boxes, EMS
Gathiruini	00239	Githunguri	Gathiruini	P.O. Boxes, Mail Services
Gathugu	00240	Githunguri	Gathugu	P.O. Boxes, Mail Services
Gatundu	01030	Gatundu	Gatundu Town	Full Services, P.O. Boxes, EMS
Gatukuyu	01028	Gatundu	Gatukuyu	P.O. Boxes, Mail Services
Kamwangi/Makwa	01009	Gatundu	Kamwangi	P.O. Boxes, Mail Services
Gituamba	01003	Gatundu	Gituamba	P.O. Boxes, Mail Services
Kanjuku	01004	Gatundu	Kanjuku	P.O. Boxes, Mail Services
Kijabe	00220	Lari	Kijabe	Full Services, P.O. Boxes, Hospital Services
Matathia	00221	Lari	Matathia	P.O. Boxes, Mail Services
Uplands	00222	Lari	Uplands	P.O. Boxes, Mail Services
Kagwe	00223	Lari	Kagwe	P.O. Boxes, Mail Services
Kabete	00625	Kabete	Kabete	Full Services, P.O. Boxes, University Services

Kiambu Post Office Hours

All Kiambu post offices operate on standard Kenya Postal Corporation hours:

• Weekdays (Monday – Friday): 8:00 AM – 5:00 PM
• Saturday: 9:00 AM – 12:00 PM
• Sunday and Public Holidays: Closed

How to Use Kiambu Postal Codes Correctly

Postal codes are essential for the sorting and delivery of mail on time, but knowing how to use them correctly will facilitate such a process even more. Just like how you write and format the Nairobi Postal address, the same format is applied when addressing mail in Kiambu County:

Standard P.O. Box Address Format

Correct format:

[Recipient Name]

P.O. Box [Number]-[Postal Code] [Town/Sub-County]

[KENYA]

Example 1: Kiambu Town Address

John Kamau

P.O. Box 1234-00900, Kiambu

Kenya

Example 2: Thika Industrial Address

ABC Manufacturing Ltd.

P.O. Box 5678-01000, Thika

Kiambu, Kenya

Example 3: Ruiru Residential Address

Mary Wanjiru

P.O. Box 9012-00232, Ruiru

Kiambu, Kenya

Where To Pay Attention: Always include the recipient’s full name on the first line. The hyphen between the box number and the postal code is mandatory (234-00900 is the correct format, not 234 00900). Include the town/sub-county name after the postal code for clarity. Add “KENYA” on the last line for international mail.

How to Apply for a P.O. Box in Kiambu

The application process to get your own P.O. Box in Kiambu is an easy process, thanks to changes that Posta Kenya has made in the previous years. The application process is now entirely online, whereby you can complete everything from your phone or computer. Before you apply for one, you need to understand that Posta Kenya offers two types of P.O. Boxes, and your choice affects costs, collection methods, and what you can use the address for.

First, there is the Physical P.O. Box (Traditional Metal Box), where, if you apply for one, you get physical keys, a designated box number, and a secure slot at your chosen post office. Lastly, there’s the Virtual P.O. Box (MPost) whereby your phone number becomes your postal address. Upon applying, you don’t get a physical box or keys; instead, you get just SMS alerts when mail arrives, and then you visit your chosen post office with your ID to collect.

All Postal Box Applications in Kenya, including for Kiambu Postal offices, are done via the Posta Kenya Application Portal at: https://apps.posta.co.ke/boxupdate/ 00902 for Kikuyu, 00217 for Limuru, and 00216 for Githunguri, etc.

Frequently Asked Questions (FAQs)