What is the ONAS fee on the water bill?

The National Sanitation Utility (ONAS) charges fees to treat wastewater and maintain municipal drainage. These are billed directly on the SONEDE invoice via a fixed quota plus a volumetric rate per cubic meter.

What difference does the meter caliber make?

A standard 15mm caliber is suited for single-family residences with lower fixed maintenance fees, whereas 20mm or 30mm calibers serve multi-unit buildings or commercial properties with higher base rates.

TunisiaUpdated for 2026Everyday life

Tunisia Water & Sanitation Bill Calculator SONEDE & ONAS 2026

Calculate quarterly potable water consumption costs with SONEDE and wastewater sanitation charges with ONAS according to official tiered tariff brackets in Tunisia.

Home Utilities & Energy Water Supply & Sewage Bills Government & Business Fees

Calculated Result

Total Water & Sanitation Bill Due

24.22TND

Calculator Inputs

Quarterly Water Consumption

Subscription Category

Water Meter Caliber

Connected to ONAS Public Sanitation

Total Water & Sanitation Bill Due

24.22TND

Net Water Consumption Charge

10 TND

Sanitation Utility Fee (ONAS)

7.5 TND

Fixed Meter Maintenance Charge

4.85 TND

VAT (7%) and Fiscal Stamp

1.87 TND

Quarterly Bill Composition

Net Water Consumption Charge

10 TND(41%)

Sanitation Utility Fee (ONAS)

7.5 TND(31%)

Fixed Meter Maintenance Charge

4.85 TND(20%)

VAT (7%) and Fiscal Stamp

1.87 TND(8%)

Calculations comply with the official tariff schedules issued jointly by the Ministry of Agriculture and Ministry of Environment for potable water and public sanitation.

Official Statute: قرارات وزارتي الفلاحة والبيئة المنظمة لتعريفات الشركة الوطنية لاستغلال وتوزيع المياه (SONEDE) والديوان الوطني للتطهير (ONAS)Last Verified: 2026-09-06

Calculation Methodology

Water utility bills are calculated quarterly on a tiered consumption progressive scale for domestic use, adding caliber meter maintenance fees, volumetric sanitation, and fiscal stamps.

Frequently Asked Questions

SONEDE bills domestic consumers on a quarterly progressive block-rate structure. The initial tier (up to 20 m³) is subsidized, and the rate per cubic meter increases progressively across higher tiers to encourage conservation.

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Tunisia

Tunisia Water & Sanitation Bill Calculator SONEDE & ONAS 2026

Calculator Inputs

Quarterly Bill Composition

Calculation Methodology

Frequently Asked Questions

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