Water Bill Calculator (Household Progressive)
Last updated: 2026-06-25
Water bill = water supply charge (progressive) + sewerage charge (progressive) + water-use charge.
Water supply and sewerage are progressive across Tier 1 (0-30 ㎥), Tier 2 (31-50 ㎥), and Tier 3 (51 ㎥+); the more you use, the higher the rate.
Enter Usage
Estimated water bill
₩0
| Item | Amount |
|---|---|
| Water supply charge (progressive) | |
| Sewerage charge (progressive) | |
| Water-use charge | |
| Total (truncated to 10 KRW) |
| Tier | Usage (㎥) | Charge |
|---|---|---|
| Tier 1 (0-30 ㎥) | ||
| Tier 2 (31-50 ㎥) | ||
| Tier 3 (51 ㎥+) |
A reference estimate using typical household progressive rates. Water supply and sewerage rates, progressive tiers, and the water-use charge differ by local government, so it may differ from your actual bill; confirm the exact amount on your local waterworks authority's bill.
How to use
- Enter usage — enter the monthly usage from your bill or water meter, in ㎥ (cubic meters).
- Check the basis — it applies household progressive rates (water supply and sewerage) plus the water-use charge. Rates differ by local government.
- View result — press Calculate to see the water supply, sewerage, and water-use charges along with the charge by progressive tier in a table.
How the water bill is calculated and what it contains
The water bill is made up of three parts: the water supply charge, the sewerage charge, and the water-use charge. The water supply charge is the cost of delivering clean tap water, the sewerage charge is the cost of treating wastewater afterward, and both are progressive, with rates rising as usage moves into higher tiers. The water-use charge is a fund for improving source-water quality, multiplying usage by a flat rate (about 170 KRW/㎥).
| Tier | Usage | Water supply (KRW/㎥) | Sewerage (KRW/㎥) |
|---|---|---|---|
| Tier 1 | 0-30 ㎥ | 580 | 400 |
| Tier 2 | 31-50 ㎥ | 790 | 930 |
| Tier 3 | 51 ㎥+ | 1,260 | 1,420 |
The progressive structure does not apply the top rate to all usage; it multiplies each tier's rate only by the usage within that tier. For example, at 40 ㎥ the first 30 ㎥ use the Tier 1 rate and the remaining 10 ㎥ use the Tier 2 rate. To check your other utilities too, use the Electricity Bill Calculator and the City Gas Bill Calculator.
Frequently Asked Questions (FAQ)
What charges make up the water bill?
The water bill is the water supply charge (tap water) + sewerage charge (wastewater treatment) + water-use charge (water-quality improvement fund). Water supply and sewerage are progressive, with rates rising as usage moves into higher tiers, while the water-use charge multiplies usage by a flat rate (about 170 KRW/㎥).
Is the water bill progressive too?
Yes, household water supply and sewerage charges are mostly progressive. This calculator splits usage into Tier 1 (0-30 ㎥), Tier 2 (31-50 ㎥), and Tier 3 (51 ㎥ and up), applying each tier's rate to its usage. The more you use, the steeper the bill as higher-tier rates apply.
Why is the water bill sometimes issued every two months?
Some local governments read meters and bill every other month (2 months). In that case the bill's usage covers two months, so to see a single month, divide the usage in half before entering it to get a rough monthly estimate.
Is this calculator accurate?
This calculator is a reference estimate using typical household progressive rates. Water supply and sewerage rates, progressive tiers, and the water-use charge differ by local government (city/county/district), so it can differ from your actual bill. Confirm the exact amount on your local waterworks authority's bill or website.
Related calculators & guides
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Korea Electricity Progressive Tariff Explained
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Last updated: 2026-06-25