How Much Does It Cost to Charge an Electric Car in MA?

A family in Framingham drives two electric vehicles. They plugged both in every night for a month without thinking much about it, then opened their Eversource bill and found it had jumped by nearly $200. The cars were doing exactly what they were supposed to do. The rate, though, was not working in anyone's favor.

That scenario plays out across Massachusetts every month. Most EV owners know roughly how much electricity to charge an electric car their model needs, but far fewer know what they are actually paying per kilowatt-hour, or whether a better option exists. Those two numbers, multiplied together, determine the real cost of driving electric. This post walks through both.

The answer depends almost entirely on the size of the battery pack. Electric vehicles are rated in kilowatt-hours (kWh), the same unit on your utility bill. A smaller commuter EV might carry a 40 to 55 kWh battery. A mid-size sedan or crossover typically lands between 60 and 82 kWh. A large truck or long-range SUV can exceed 100 kWh.

In practice, you rarely charge from completely empty to completely full. Most drivers top up from 20 percent to 80 percent, which is the range battery management systems prefer. That means a 75 kWh battery typically pulls about 45 kWh from the wall during a typical evening charge, not the full 75. Add a small efficiency loss from the charger itself (usually 10 to 15 percent), and a realistic draw for that same car is closer to 48 to 52 kWh.

Quick reference by vehicle size:

Small EV (40 kWh pack, 20-80% charge): roughly 26 to 29 kWh per session
Mid-size EV (75 kWh pack, 20-80% charge): roughly 48 to 52 kWh per session
Large EV or truck (100+ kWh pack, 20-80% charge): roughly 65 to 72 kWh per session

Your car's onboard display or companion app will show actual energy consumed per charge, which is the most accurate figure to use when calculating your costs.

Once you know how many kWh a charge session pulls, the math is straightforward: multiply by your rate per kWh.

As of August 2026, the utility Basic Service (default supply) rates in Massachusetts are:

Eversource: approximately 17.3 cents per kWh
National Grid: approximately 17.2 cents per kWh
National Grid (Nantucket): approximately 17.2 cents per kWh

The lowest competitive supplier rate currently available in the state is approximately 15.7 cents per kWh, though that varies by utility territory. Check the Massachusetts electricity page on ElectricRates.org for current figures in your area.

Sample charging costs at Basic Service rates (Eversource, 17.3 cents/kWh):

Small EV, ~28 kWh session: approximately $4.84
Mid-size EV, ~50 kWh session: approximately $8.65
Large EV/truck, ~68 kWh session: approximately $11.76
Full charge, 100 kWh pack: approximately $17.30

At the lowest competitive supplier rate (15.7 cents/kWh):

Small EV, ~28 kWh session: approximately $4.40
Mid-size EV, ~50 kWh session: approximately $7.85
Large EV/truck, ~68 kWh session: approximately $10.68
Full charge, 100 kWh pack: approximately $15.70

The difference per session looks modest. Spread across 20 or more charges per month, and it adds up to a meaningful annual savings.

Most households with one EV charge at home somewhere between 15 and 25 times per month, depending on driving habits and how often they top up at public stations.

Using a mid-size EV with roughly 50 kWh per home charge session:

At Eversource Basic Service (17.3 cents): 20 sessions comes to approximately $173 per month, or just over $2,070 per year.
At the lowest competitive supplier rate (15.7 cents): the same 20 sessions runs approximately $157 per month, or about $1,884 per year.

That is a rough difference of around $192 annually for one car on one rate change, with no change to driving habits whatsoever. A two-EV household could see roughly double that gap.

Keep in mind these figures reflect supply cost only. Your total electricity bill also includes the utility's delivery charge, which covers the poles, wires, and grid infrastructure. Delivery rates are set by the Massachusetts Department of Public Utilities and are the same regardless of which supplier you choose. Only the supply portion is open to competition.

Basic Service is the default supply rate set by your utility, Eversource or National Grid, and approved by the Massachusetts Department of Public Utilities (DPU). It changes on a schedule, typically every six months for residential customers. It is never a penalty rate, but it is also not designed to be the cheapest option available.

Competitive suppliers are third-party companies licensed by the DPU to sell electricity supply in Massachusetts. They can offer fixed rates (locked for a contract term), variable rates, green energy products, or combinations. The lowest rate in the market as of August 2026 runs about 1.6 cents per kWh below the Eversource Basic Service rate.

For EV owners, a fixed competitive rate has a specific appeal: your charging cost becomes predictable. Basic Service fluctuates. If you know you will consistently add 800 to 1,000 kWh per month in EV charging, a fixed rate at a meaningful discount is worth evaluating.

The state comparison tool is Energy Switch Massachusetts, run by the state. It lists DPU-licensed suppliers and their current offers side by side. Before signing with any supplier, read the contract length, any early termination fee, and whether the rate is truly fixed or introductory. ElectricRates.org also lists live offers at the Massachusetts comparison page.

Both Eversource and National Grid offer time-of-use (TOU) rate options for residential customers. Under these plans, the per-kWh rate is lower during off-peak hours, typically overnight, and higher during peak afternoon and evening hours when grid demand is greatest.

For an EV owner who can schedule charging to run between roughly 11 p.m. and 7 a.m., TOU pricing can reduce the effective supply rate paid on charging kilowatt-hours considerably. The specific rate tiers and hour windows differ by utility and rate plan. Contact Eversource or National Grid directly, or review their rate schedules on file with the DPU, to see current TOU structures.

The practical step is simple: most EVs and home chargers allow you to schedule charging start times from an app. Set it to begin after 11 p.m., and the car handles the rest. Combined with a competitive supplier rate during off-peak windows, some households see their effective per-kWh charging cost drop noticeably below the Basic Service figure.

Public Level 2 and DC fast chargers in Massachusetts are priced by the network operator, not by the utility. Pricing structures vary: some charge per kWh, some per minute, some by session. The per-kWh cost at public stations is almost always higher than at home, often significantly so.

DC fast chargers at highway corridors can run anywhere from a moderate premium above home rates to multiples of the residential rate, depending on the network and membership status. Per-minute pricing makes comparison harder, because a slower car on a fast charger pays more per kWh effectively.

The takeaway for most Massachusetts drivers: home charging is the cost baseline to optimize. Public charging is a convenience you pay extra for, not a replacement for a good home rate. Maximizing the percentage of miles charged at home on an optimized rate is the single highest-leverage move for EV operating costs.

Massachusetts has several programs that can lower overall electricity costs for income-qualified residents, which in turn lowers the effective cost of EV charging.

The Low Income Home Energy Assistance Program (LIHEAP) provides heating assistance and, in some cases, can free up household budget that would otherwise go toward energy bills. Eversource and National Grid both offer discount rate programs for qualifying low-income customers that reduce the delivery portion of the bill. The income thresholds and application processes differ by utility.

The Massachusetts Clean Energy Center (MassCEC) has also run incentive programs related to EV adoption and charging equipment. Program availability changes, so check directly with MassCEC, your utility's website, or the DPU for the most current offerings. ElectricRates.org does not administer any of these programs; those links are here for reference.

You do not need an advanced formula. Follow these four steps:

1. Find your rate. Look at your most recent electricity bill. The supply charge per kWh is listed separately from the delivery charge. That supply number is what competitive offers will replace if you switch.

2. Find your average charge session size. Your EV's app or trip log will show kWh consumed. Average several charges for a realistic figure.

3. Multiply. kWh per session times your rate equals cost per session. Multiply by monthly sessions for your monthly charging cost.

4. Compare. Plug the same kWh number into current competitive rates at ElectricRates.org or Energy Switch Massachusetts. The difference is your potential savings.

This exercise takes about five minutes and gives you a concrete number, not a guess. EV owners who do it consistently tend to make better decisions about both charging habits and supplier choices.