Estimate your Mombasa Water and Sewerage Company (MOWASSCO) bill from your monthly water consumption, using the WASREB-approved Domestic/Residential tariff.
A Mombasa Water bill combines two charges on the same metered consumption: the water charge itself, and a sewerage charge billed on 75% of that same volume — priced through the same tariff table as the water charge, not a separate rate. This calculator applies the WASREB-approved MOWASSCO Domestic/Residential tariff so you can check a bill or estimate the next one before it arrives.
How Is the Mombasa Water Charge Calculated?
Mombasa Water Supply and Sanitation Company (MOWASSCO) bills domestic consumption across six blocks, so each cubic metre is charged at its own block's rate rather than one flat rate for your whole bill. The first 1–6 m³ costs KES 150/m³, 7–20 m³ costs KES 182/m³, 21–50 m³ costs KES 190/m³, 51–100 m³ costs KES 210/m³, 101–300 m³ costs KES 220/m³, and anything above 300 m³ costs KES 250/m³.
| Consumption Block (m³) | Domestic/Residential Rate (KES/m³) |
|---|---|
| 1–6 | 150 |
| 7–20 | 182 |
| 21–50 | 190 |
| 51–100 | 210 |
| 101–300 | 220 |
| >300 | 250 |
How Is the Sewerage Charge Calculated?
Sewerage is billed on 75% of your metered water volume, priced through the same six-block tariff used for the water charge above — not a cheaper, separate sewerage rate table like some other Kenyan utilities use. A household using 20 m³ of water is billed sewerage on 15 m³, run through those same blocks.
What Happens If My Meter Isn't Read?
MOWASSCO bills a customer whose meter is non-functional using the average of that customer's own last three months' bills, rather than a fresh estimate. Report a faulty meter promptly, since the averaged bill continues until MOWASSCO repairs or replaces it.
How Do I Pay My Mombasa Water Bill via M-Pesa?
Go to M-Pesa, select Lipa na M-Pesa > Pay Bill, enter Business Number 895500, then enter your MOWASSCO account number before confirming the amount and your M-Pesa PIN. You can also dial *873*001# to check and pay your bill directly by USSD.
How Do I Use This Calculator?
Enter your monthly water consumption in cubic metres (m³), found on your MOWASSCO bill or read directly off your meter, and the calculator returns your water charge, sewerage charge, and total bill instantly. It covers only the metered Domestic/Residential charge — it doesn't add one-off items like a new connection fee, water deposit, or reconnection penalty, which MOWASSCO bills separately.
Does a Multi-Dwelling Unit (MDU) pay the same rate as a single domestic connection?
No — MOWASSCO bills Multi-Dwelling Units at a flat KES 182 per cubic metre regardless of volume, while a single Domestic/Residential connection moves through six increasing price blocks from KES 150 to KES 250 per cubic metre as consumption rises.
What if I have a sewer connection but no water connection?
A single-dwelling domestic customer with sewerage but no water connection pays a flat KES 350 per month. Every other customer category without a water connection is still charged 75% of the volume metered at their own separate water source, priced through the same tariff table.
How much is a new Mombasa Water connection or deposit?
MOWASSCO charges KES 2,500 for a new domestic water connection and a separate KES 2,500 domestic water deposit, plus KES 2,500 for a residential sewer connection if you're adding sewerage at the same time.