Vehicle EconomicsAnnual EV Electricity Cost
Is your monthly EV charging budget actually enough?
Why this comes up
A round-number charging budget like "$50 a month" is a guess, not a calculation, and it's an easy guess to make because a gas budget habit ("I spend about $150 a month on gas") doesn't translate cleanly to an EV, where the cost depends on your specific charging mix, efficiency, and rates rather than a single price you see posted at every pump. This engine turns your actual charging inputs into a true monthly target and checks it against what you've actually budgeted, the same way Maintenance Cost Budget checks a maintenance reserve against a planning figure instead of a guess.
How we calculated this
Annual cost uses the same fuel and charging cost model as EV Home Charging Cost: energy needed at the battery, adjusted for charging efficiency, blended across your home and public charging shares at their respective rates. The monthly target is that annual cost divided by 12, compared against your entered monthly budget to produce a gap, positive if you're underfunded, negative if your budget already covers more than you'll actually spend.
Worked example, using this page's own defaults: the true annual cost is$784, a monthly target of $65.33, against a $50 budget, a shortfall of about $15.33 a month.
What this means
- A round-number charging budget ("$50/month") is rarely the real number once your actual charging mix and rates are computed, treat this figure as the one to actually plan around, not the guess that started the conversation.
- If you're underfunded, either raise your budget to match reality or shift more charging toward the cheaper home rate, see Public vs Home Charging Cost to size that shift directly.
- Recompute the underlying cost on its own in EV Home Charging Cost if you want to explore rate assumptions with a live slider instead of a fixed budget comparison.
Limitations
No current electricity rate is assumed or fetched, every rate here is what you entered, and the model assumes a steady charging mix across the year rather than seasonal swings in driving or a temporary change in where you charge. See Methodology.
Methodology
This engine is built on Vehicle Economics' fuel and charging cost model: your own miles, MPG or kWh, and rates converted directly to a dollar cost. See Methodology for the full detail.