Charging at night saves money only if your electricity connection is billed on a time-of-day (ToD) tariff — and many Indian homes are not. Some DISCOMs charge less per unit during off-peak hours, which often fall late at night, and more during the evening peak. Others bill one flat rate around the clock, so a unit consumed at 2 am costs exactly what it costs at 7 pm. The check is simple: look at your electricity bill for slot-wise consumption, or ask your DISCOM whether a ToD tariff applies to your connection category. And even on a flat rate, night charging still helps — it keeps your car off the building's wiring during the evening rush.
What a time-of-day tariff actually is
A ToD tariff splits the day into slots and prices each slot differently. The idea is to nudge consumption away from hours when the grid is strained — typically evenings, when homes switch on lights, ACs and pumps — and towards hours when demand is low or generation is plentiful. Under such a tariff, the same unit of electricity can cost noticeably more in one slot and noticeably less in another.
Two things trip people up. First, ToD is not universal: whether it exists, which hours count as off-peak, and whether it applies to ordinary residential connections all vary by DISCOM and change over time. Second, "off-peak" does not automatically mean "night". Some tariff structures place the cheapest hours in the daytime, when solar generation is high. So treat "night is cheaper" as a hypothesis to verify against your own bill, not a rule.
How to check whether your connection gets ToD rates
- Read your latest bill line by line. If ToD applies to you, the bill usually shows consumption split across time slots, or separate peak and off-peak lines, rather than a single units figure.
- Look at your meter. Slot-wise billing needs a meter that records when you consumed, not just how much. Many newer smart or static meters can; older meters often cannot.
- Ask your DISCOM directly. Customer care or the DISCOM's published tariff schedule will tell you whether a ToD tariff exists for your connection category, whether it is optional or compulsory, and what the current slot timings are. Timings and rates get revised, so check the current schedule rather than relying on an old forum post.
- Note the peak hours too. A ToD tariff cuts both ways: cheap off-peak units usually come with costlier peak units. If your habit is to plug in at 7 pm when you get home, a ToD tariff could make charging more expensive, not less, unless you shift the session later.
In an apartment, "whose meter" matters as much as "what time"
In an independent house, your tariff is your tariff. In a society, the electricity feeding your charger might come through your flat's meter, a separate sub-meter, or the society's common-area connection — and each can sit in a different tariff category. If you charge at a shared charger billed at a fixed internal rate per unit, the DISCOM's ToD slots may never reach your wallet unless the RWA chooses to pass them on. The differences between these setups are covered in our guides to sub-meter versus smart-charger billing and private versus shared charging in apartment parking.
| Your charging setup | Whose tariff decides the rate | Can ToD cut your cost? | What to check first |
|---|---|---|---|
| Charger wired to your own flat meter | Your residential tariff | Yes, if your DISCOM offers ToD for your category | Your bill and meter type; confirm with the DISCOM |
| Charger on a separate sub-meter in your name | The tariff category of that connection | Possibly — its category may differ from your flat's | How the sub-meter connection is classified |
| Charger on the society's common-area meter | The society's connection tariff | Only if that tariff has ToD and the RWA passes it on | How the RWA bills members for charging units |
| Shared smart charger billed per session | Whatever internal rate the society sets | Only if the per-unit rate varies by time | The published rate card and billing rules |
A worked example — with illustrative numbers
Say your EV uses about 15 units per 100 km and you drive 1,000 km a month — roughly 150 units of charging. These are round example figures; your car's real consumption will differ.
- Flat tariff: say your rate is ₹8 per unit (check your own bill). Monthly charging cost is about 150 × ₹8 = ₹1,200, whatever the hour.
- Illustrative ToD tariff: suppose off-peak units cost 20% less (₹6.40) and peak units 20% more (₹9.60). Charging entirely off-peak works out to about ₹960 a month; charging entirely in peak hours, about ₹1,440. In this example, deliberate timing is worth about ₹480 a month — real gaps depend entirely on your DISCOM's actual slot rates.
To run the arithmetic with your own numbers, use the monthly charging cost calculator, and see how to calculate monthly EV charging cost for the formula written out.
No ToD tariff? Night charging still earns its keep
Even when every unit costs the same, when you charge still matters in a society. Evenings are when a building's load peaks — lifts, pumps, ACs, kitchens — and adding several EVs to that same window stresses wiring, transformers and the society's sanctioned load. Charging after the evening peak spreads the load, which makes it easier for an RWA to say yes to more chargers and weakens the case for expensive infrastructure upgrades.
Night charging also pairs naturally with slower chargers. A modest charger running through the night replenishes far more range than most people drive in a day, which is why many apartment users never need the bigger unit — the trade-offs are laid out in our comparison of 3.3 kW versus 7.2 kW charging.
A simple decision flow
- Whose meter feeds your charger — yours, a sub-meter, or the society's?
- Does that connection's tariff have ToD slots? Check the bill; confirm with the DISCOM.
- No ToD: charge at night anyway for building-load reasons; timing won't change your bill.
- ToD exists: note the exact off-peak window and shift charging into it. A charger with a scheduling function, or the vehicle's own charge timer, does this without anyone staying awake.
- ToD exists but the society bills a flat internal rate: raise it with the RWA — a time-linked internal rate lets residents who shift their charging share the benefit.
Common questions
Does having a smart meter mean I automatically get cheaper night rates?
No. A slot-capable meter is a precondition, not the tariff itself. The meter records when you consumed; whether those slots are priced differently depends on the tariff applied to your connection. Confirm with your DISCOM.
Can charging in the evening actually cost more than daytime?
Under a ToD tariff, yes — evening hours are commonly priced as peak, so a plug-in-at-7-pm habit can be the most expensive way to charge. On a flat tariff, the hour makes no difference to your bill.
My society charges one fixed rate per unit at the shared charger. Does timing matter for me?
Not for your wallet, as long as the internal rate stays flat. It still matters for the building: off-peak sessions reduce evening strain and queueing at the charger. If the society's own connection is on ToD, it may be worth proposing an internal rate that reflects it.
Is it safe to leave an EV charging unattended overnight?
A properly installed charger on a dedicated, protected circuit is designed for unattended charging, and the car's own battery management ends the session when full. The real safety question is installation quality — earthing, breaker sizing, cable routing — which our apartment EV charging safety checklist walks through.
One last thing: tariff schedules, slot timings and metering rules are revised periodically and differ between DISCOMs, so confirm the current position with your own DISCOM before planning around it. And any wiring, sub-meter or charger installation decision should be taken with a licensed electrician who has seen your building's actual electrical setup.