Nairobi GPO (General Post Office), situated in Kenya’s capital city, serves as the national hub for postal services and operates under the Postal Corporation of Kenya (Posta). Its primary postal code, 00100, is crucial for efficient mail delivery, business operations, and access to government services throughout Nairobi County. It was established during the colonial era, and the GPO has evolved into a modern facility handling international and domestic mail, leveraging Kenya’s five-digit postal system, where the first two digits 00 denote Nairobi’s central region.
Nairobi GPO Postal Service Overview
| Information | Details |
| Primary Postal Code | 00100 |
| Parent County | Nairobi City County |
| Main Post Office Location | General Post Office (GPO), Posta House, Kenyatta Avenue, Nairobi CBD |
| Number of Post Offices | 6 |
| Postal Code(s) Structure | 5-digit codes. |
Postal System & Mail Delivery in Nairobi GPO
The postal system functioning within the Nairobi Central Business District is fundamentally distinct from systems that provide direct-to-door mail delivery. It operates on a centralized model that is entirely P.O. Box-centric.
All mail, whether letters or parcels, is delivered to a secure Post Office Box rented by an individual or organization at a specific post office branch.
The correct postal address is not determined by the recipient’s physical street location but by the branch at which their P.O. Box is registered.
This system creates a crucial distinction between a physical address and a mailing address. For instance, two companies operating from the same building on Haile Selassie Avenue could have entirely different postal codes.
If one rents a box at the General Post Office, its mailing address will use the 00100 code. If it’s neighbor rents a box at the City Square Post Office, located just across the street, its mailing address will use the 00200 code.
This demonstrates that senders cannot reliably infer a postal code from a street address alone; the recipient must provide their exact P.O. Box number and the corresponding code for that specific postal branch.
The post offices within the CBD, led by the GPO, offer a range of services including traditional mail, Express Mail Service (EMS) for expedited shipping, and P.O. Box rentals.
Nairobi GPO Postal Offices
The Postal Corporation of Kenya manages six postal offices in the Nairobi CBD region. They are as follows, along with their Postal codes:
| No. | Office Name | Type | Location / Address | Services Offered | Postal Code |
|---|---|---|---|---|---|
| 1 | Nairobi G.P.O. | General Post Office | Posta House, Kenyatta Avenue | Mail, EMS, P.O. Box Rental, M-Posta, Huduma Centre | 00100 |
| 2 | City Square Post Office | Post Office | Haile Selassie Avenue | Mail, EMS, P.O. Box Rental | 00200 |
| 3 | Ronald Ngala Street Post Office | Post Office | Ronald Ngala Street | Mail, EMS, P.O. Box Rental | 00300 |
| 4 | Tom Mboya Street Post Office | Post Office | Emperor Building, Tom Mboya Street | Mail, EMS, P.O. Box Rental, Banking Services, Bill Payment | 00400 |
| 5 | Jamia Post Office | Post Office | Kigali Road (near Jamia Mosque) | Mail, EMS, P.O. Box Rental | 00101 |
| 6 | State Law Post Office | Designated Code (non‑public) | State Law Office | P.O. Box services for government legal departments | 00102 |
Other Popular Postal Codes for Institutions in the Nairobi CBD are as follows:
| No. | Place Name (Official) | Category | Location / Area (Geo‑verified) | Postal Code |
|---|---|---|---|---|
| 1 | Office of the Attorney General & Department of Justice (Sheria House) | Government Office | Sheria House, Harambee Avenue | 00100 |
| 2 | Parliament of Kenya (National Assembly & Senate) | Government Office | Parliament Buildings, Parliament Road | 00100 |
| 3 | Supreme Court of Kenya | Government Office | Supreme Court Building, City Hall Way | 00100 |
| 4 | Nairobi City County Head Office (City Hall) | Government Office | City Hall, City Hall Way | 00100 |
| 5 | Kenya Revenue Authority (KRA) Headquarters (Times Tower) | Government Office | Times Tower, Haile Selassie Avenue | 00100 |
| 6 | The National Treasury and Economic Planning (Treasury Building) | Government Office | Treasury Building, Harambee Avenue | 00100 |
| 7 | Ministry of Foreign and Diaspora Affairs (Old Treasury Building) | Government Office | Old Treasury Building, Harambee Avenue | 00100 |
| 8 | Huduma Centre GPO (General Post Office Building) | Service Centre | Posta House, Kenyatta Avenue | 00100 |
| 9 | Kenyatta International Convention Centre (KICC) | State Corporation | Harambee Avenue | 00100 |
| 10 | Central Bank of Kenya (CBK) Headquarters | Financial | Haile Selassie Avenue | 00200 |
| 11 | KCB Bank Group Headquarters (Kencom House) | Financial | Kencom House, Moi Avenue | 00100 |
| 12 | National Bank of Kenya Headquarters (National Bank Building) | Financial | Harambee Avenue | 00200 |
| 13 | I&M Bank, Kenyatta Avenue Branch (I&M Bank Tower) | Financial | Kenyatta Avenue | 00100 |
| 14 | Standard Chartered Bank, Kenyatta Avenue Branch | Financial | Standard Chartered Building, Kenyatta Ave | 00100 |
| 15 | Co-operative Bank of Kenya, Co‑op House Branch | Financial | Haile Selassie Avenue | 00200 |
| 16 | The Karen Hospital, Cardinal Otunga Branch | Healthcare | Kaunda Street | 00200 |
| 17 | Meridian Equator Hospital, Moi Avenue | Healthcare | Moi Avenue | 00100 |
| 18 | University of Nairobi, Main Campus | Education | University Way | 00100 |
| 19 | Kenyatta University, City Centre Campus | Education | Haile Selassie Avenue | 00100 |
| 20 | Technical University of Kenya | Education | Haile Selassie Avenue | 00100 |
| 21 | Kenya Methodist University (KEMU), Nairobi Campus | Education | KEMU Towers, University Way | 00100 |
| 22 | Nairobi City Market | Market | Muindi Mbingu & Koinange Streets | 00100 |
| 23 | Imenti House (Commercial Centre) | Commercial Centre | Tom Mboya Street | 00400 |
| 24 | Nation Centre (Commercial Centre) | Commercial Centre | Kimathi Street | 00100 |