Utility bill calculator 2026: water, gas, electricity — what's the cost?
RentTab · Published: 30 June 2026
Utility bills are calculated per service with the consumption × unit price formula: take the difference between the previous and current meter readings (water, gas, electricity) and multiply by the unit price; add the fixed charges (waste, service charge). The calculator below works out water instantly; the other utilities and per-tenant splitting are automatic in RentTab. (The context is Hungarian; adapt to your market.)
Calculate the water charge
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The calculator works out the water charge from the readings and unit price you enter. Gas, electricity, district heating and fixed charges — plus splitting across multiple tenants — are available in the RentTab app.
How the calculator works
Water is the simplest metered utility:
Water charge = (current reading − previous reading) × unit price
The unit price bundles water and sewage together (most bills show it per m³). Example: 18 m³ × 1,420 Ft/m³ = 25,560 Ft.
The other utilities: same logic
Every metered utility follows consumption × unit price, just with a different unit:
- Gas: m³ consumption → often converted to kWh (with a correction factor), then × unit price
- Electricity: kWh consumption × unit price (by tariff)
- District heating: by GJ or air-cubic-metre
- Waste, service charge: typically a fixed monthly fee, not consumption-based
RentTab tracks all of them in one place and produces the monthly settlement automatically — including the utility settlement for rentals and the who pays what split.
Multiple tenants? Split by meter
With several tenants in one flat, the bills must be split per head or by consumption — easy to get wrong by hand. RentTab computes it per tenant from the meter readings, so every month it’s clear who owes what.
Frequently asked questions
How do I calculate the water charge? The difference between the current and previous reading is the consumption (m³), which you multiply by the water + sewage unit price. The calculator does this instantly.
Why does only water calculate here? Water is the simplest example. Gas, electricity, district heating, fixed charges — and per-tenant splitting — are available in the RentTab app, where every utility sits in one place.
How much is the water unit price in 2026? It depends on the provider and municipality; you’ll find the exact per-m³ price on your own water bill and can enter it in the calculator.
Is sewage included in the water charge? On most bills water and sewage are shown together per m³ — enter the sum of the two in the unit price field.