Your TNB bill, explained — and what solar changes
Enter your bill or your kWh. See exactly which charges make it up, which threshold you are sitting above, and what the bill becomes with a rooftop system.
Priced on TNB's domestic tariff effective 1 July 2025, with AFA +3.67 sen/kWh for September 2026. Time-of-Use supported.
That is about 896 kWh a month.
Only if you have an activated smart meter. Peak is 2pm–10pm on weekdays.
Now add solar
Share of your electricity used 8am–5pm. Typical: 30% if the house is empty by day, 60% if someone works from home.
Bill now
RM 450.08
50.2 sen/kWh effective
With 5 kW solar
RM 160.09
after RM 109.67 export credit
Saving RM 289.99 a month — RM 3,480 a year.
You are 296 kWh above the 600 kWh line
Above it, AFA, RM10 retail charge and 8% service tax all start. Crossing that line costs RM 42.12/month for a single extra kWh. A 5 kW system does not get you back under it — try a larger system or a higher daytime share.
You are only 104 kWh below the 1,000 kWh line, where Energy Efficiency Incentive stops. One hot month could cross it.
What you are actually being charged
| Energy charge27.03 sen/kWh x 896 | RM 242.19 |
| Automatic Fuel Adjustment (AFA)+3.67 sen/kWh x 896 | RM 32.88 |
| Capacity charge4.55 sen/kWh x 896 | RM 40.77 |
| Network charge12.85 sen/kWh x 896 | RM 115.14 |
| Retail chargeRM10.00 per month | RM 10.00 |
| Energy Efficiency Incentive-1.0 sen/kWh x 896 | −RM 8.96 |
| Service tax (8%) | RM 11.15 |
| KWTBB (1.6%) | RM 6.91 |
| Total | RM 450.08 |
The 600 kWh line is why your bill jumped
Malaysian domestic electricity is not billed on a smooth curve. Three reliefs disappear the moment monthly consumption passes 600 kWh, and they disappear together:
- AFA starts applying — and to every kWh you used that month, not only the ones above the line.
- The RM10 retail charge is no longer waived.
- The 8% service tax exemption is lost on consumption above 600 kWh.
At exactly 600 kWh the bill is RM 215.98. One kilowatt-hour more and it is RM 258.10 — RM 42.12 for a single unit. A second line sits at 1,500 kWh, where the energy charge steps from 27.03 to 37.03 sen on every kWh: that one costs RM 160.24.
This is what makes solar behave differently here than in a flat-tariff market. A system that takes a household from 700 kWh to 400 kWh does not just remove 300 kWh of energy — it restores all three reliefs and moves the home into a much better Energy Efficiency Incentive band. The saving is a step, not a slope, which is also why an average-rate estimate understates it.
Where these numbers come from
Every figure on this page is computed from TNB's published domestic schedule, not from a stored estimate. The tariff has eight moving parts and this models all of them: energy, capacity and network charges, the Automatic Fuel Adjustment, the Energy Efficiency Incentive band, the RM10 retail charge, KWTBB and the 8% service tax — each with its own exemption threshold.
One caution worth knowing when you compare answers elsewhere: TNB restructured on 1 July 2025 and the old tiered blocks — 21.8 sen for the first 200 kWh, 33.4 for the next 100, 51.6 above that — no longer exist. A number of guides and calculators still publish them. They understate high bills, because the old top block was cheaper than the current all-in rate once AFA and service tax apply.
AFA is the only component that changes month to month. It is checked daily against the published rate and this page names the month it is billing, so a stale figure is visible rather than silent.
TNB bill questions
Why is my TNB bill so high?
Usually because you crossed 600 kWh. Below that line TNB waives the Automatic Fuel Adjustment, waives the RM10 monthly retail charge, and exempts you from the 8% service tax. Above it all three apply — and the AFA applies to every kWh you used, not just the ones above the line. At exactly 600 kWh the bill is RM 215.98; at 601 kWh it is RM 258.10. That is RM 42.12 for one extra unit of electricity.
Is solar worth it if my TNB bill is below RM400?
Often yes, but the payback is slower and the sizing matters more. Below about RM400 a month you are using roughly 800 kWh or less, so a large system spends most of its output exporting at 27 sen instead of displacing electricity you would have paid 49 sen for. The system that pays back fastest on a smaller bill is a smaller one matched to your daytime use — which is what the calculator above is showing you when a bigger slider stops improving the result.
How much does solar reduce a TNB bill?
Self-consumption typically removes 45–55% of the bill directly, and export credits offset much of the rest, so a well-matched system commonly takes a bill down by 70–90% net. The exact figure depends far more on how much electricity you use during daylight hours than on how many panels you fit — a household that is empty from 8am to 6pm self-consumes far less of what it generates.
What is AFA on my TNB bill?
The Automatic Fuel Adjustment — a monthly surcharge or rebate set by the Energy Commission that tracks fuel costs. It is currently +3.67 sen/kWh for September 2026. It was a rebate for the first ten months after the July 2025 restructure and turned into a surcharge in May 2026, which is a large part of why bills have risen. Households at 600 kWh and below do not pay it at all.
Does this use the current TNB tariff?
Yes — the domestic tariff effective 1 July 2025, which replaced the old tiered blocks entirely. Energy at 27.03 sen/kWh up to 1,500 kWh and 37.03 above, plus capacity 4.55 and network 12.85 sen/kWh, plus AFA, the Energy Efficiency Incentive, the RM10 retail charge, KWTBB and 8% service tax where each applies. Many guides still publish the pre-2025 bands (21.8 / 33.4 / 51.6 sen and so on); those rates no longer exist and will understate a large bill.
How do I calculate my TNB bill from kWh?
Multiply your kWh by the energy rate — 27.03 sen up to 1,500 kWh a month, 37.03 sen above it — then add capacity at 4.55 sen and network at 12.85 sen on every kWh. Above 600 kWh add the AFA on all your consumption, the RM10 retail charge, 8% service tax on the portion above 600 kWh, and 1.6% KWTBB. Then subtract the Energy Efficiency Incentive if you used 1,000 kWh or less. Switch the calculator above to kWh mode and it does all of that and shows each line.
Is this a residential or commercial TNB calculator?
Residential. It prices the Domestic tariff, including the Domestic Time-of-Use option, and the exemptions that only domestic customers get — the 600 kWh AFA and retail waiver, the Energy Efficiency Incentive, and the KWTBB exemption below 300 kWh. Commercial supply runs on entirely different tariff classes with no such exemptions, so putting business figures through this would be wrong. For commercial rooftop solar under Solar ATAP, see the commercial guide linked below.
Should I switch to the Time-of-Use tariff?
Only if you can genuinely shift load out of the 2pm–10pm weekday peak, and only with an activated smart meter. ToU replaces the energy component with 28.52 sen peak and 24.43 sen off-peak below 1,500 kWh. It rewards running the washing machine, dryer and water heater overnight or at weekends. Toggle it in the calculator to see whether your own peak share makes it worthwhile — for many households it does not.
Next steps
Estimates only, not a bill prediction or a quotation. Figures follow TNB's published domestic tariff effective 1 July 2025 and the Energy Commission's monthly AFA; your actual bill depends on your meter reading and billing period. For the authoritative figure use myTNB. SolarAtapMY is independent and not affiliated with TNB or SEDA.