For building-managed EV charging
See full charge cost before you plug in.
If your building chooses the charging provider, its advertised energy rate is only part of the bill. Enter energy, session, time, and idle fees. See whole session total, effective £/kWh, and cost per 100 miles.
- Payment
- £29 one-time
- Subscription
- No subscription
- Access
- No account
- Privacy
- Inputs stay in browser
Example · 35 kWh
Energy + fixed + time fees
£21.70
Provider rate
£0.52/kWh
Effective rate
£0.62/kWh
Shown first
Energy price
Added later
Session + time + idle fees
Compare this
Whole session cost
Official sources. Simple arithmetic.
How EV charging fees reach your bill
What an EV charging session actually costs
Read energy, time, session, and other fees as one bill—not four unrelated numbers.
Open guide →Idle fees: find the trigger before you plug in
Separate charging time from occupancy time and forecast the fee provider can add after charging changes state.
Open guide →Compare charging providers without trusting headline rate
Normalize different tariffs against same charging session and same payment route.
Open guide →No account or provider connection
Copy tariff. Check one session.
- 01Find tariffCopy energy rate, session fee, time fee, and idle rule.
- 02Enter sessionAdd energy, expected fees, and vehicle consumption.
- 03Read full costCompare whole bill, effective £/kWh, and cost/100 miles.
Direct answers
EV charging cost questions
- What does an EV charging session cost?
- Session cost is energy added multiplied by energy rate, plus fixed session, time, and idle fees. ChargeWindow adds those amounts before calculating effective price per kWh.
- Why is effective price per kWh higher than charger price?
- Charger price often shows energy only. Effective price per kWh divides whole session bill, including fixed and time-based fees, by energy delivered.
- How do idle fees change charging cost?
- Idle fees add cost after provider-defined trigger, often charging completion or grace-period expiry. Exact trigger, unit, cap, and stop condition come from provider tariff.
- Does ChargeWindow use live charger prices?
- No. ChargeWindow calculates tariff values you enter. Charger, provider app, or building notice remains source for current station price and terms.
One-time tool · £29