TNB Bill Charges Explained Line by Line (RP4) | Cobler
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Your TNB Bill, Line by Line
Each line of a TNB bill is a meter reading multiplied by a price. Follow the five RP4 charges (energy, capacity, network, retail and AFA), plus the power factor surcharge and KWTBB, through the September 2026 bills of an example office tower and shoplot.
Every month a TNB bill arrives, and most people look only at the total. But the total is a sum of separate charges, and each one is worked out in a different way. So where does each number on the bill come from?
For a non-domestic customer in Peninsular Malaysia, the TNB bill charges are built from five main lines: energy, capacity, network, retail and the Automatic Fuel Adjustment (AFA). A power factor surcharge is added only when the power factor is too low, and a renewable energy levy (KWTBB) and any tax come after that. Almost every line is one of the three meter readings from Part 15 multiplied by a price. In this part we go through the lines one at a time, then work out the September 2026 bills of our two example buildings.
Step 1: The bill starts with three meter readings and a tariff
The meter gives the bill three numbers. Part 15 explained how it measures each one:
Energy (kWh): the total energy used in the month.
Maximum demand (kW): the highest 30-minute average power in the month.
Power factor: worked out from the kWh and the reactive energy (kVARh) the meter records.
The tariff sets the price for each reading. Your tariff depends on how your building is supplied (Part 14): low voltage (LV) or medium voltage (MV), and General or Time-of-Use (ToU). All prices in this part are from RP4, the TNB (Tenaga Nasional Berhad) tariff structure in force since 1 July 2025 (). Cobler's guide to explains how a building is placed in one.
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We use our two fictional example buildings throughout Cobler's courses:
Our example office tower in Kuala Lumpur: 20 storeys, supplied at 11 kV, on the MV non-domestic General tariff. In September 2026 it used 500,000 kWh, its maximum demand was 1,600 kW and its power factor was about 0.92.
Our example shoplot in Petaling Jaya: three storeys with a café and a small office, supplied at 400/230 V, on the LV non-domestic General tariff. In September 2026 it used 8,000 kWh.
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A fictional sample bill, not a real TNB bill. Each charge is coloured to match the meter reading it comes from.
The official tariff schedule names the charges in Malay: Caj Tenaga (energy), Caj Kapasiti (capacity), Caj Rangkaian (network) and Caj Peruncitan (retail). For a detailed tour of a real bill's layout, see how to read your TNB electricity bill.
Step 2: The energy charge pays for each kWh
The energy charge is your kWh multiplied by a rate in sen per kWh. Rates are quoted in sen, and 100 sen make RM1, so the last step is to divide by 100.
MV General: 29.83 sen/kWh.
LV General: 27.03 sen/kWh.
Working out the two example bills:
Office tower: 500,000 kWh × 29.83 sen = 14,915,000 sen = RM149,150
Shoplot: 8,000 kWh × 27.03 sen = 216,240 sen = RM2,162.40
On a ToU tariff, the meter splits the kWh into peak and off-peak, and each part has its own rate. The peak window is 2pm to 10pm, Monday to Friday. All other hours are off-peak, and weekends are off-peak throughout. MV ToU charges 31.32 sen/kWh at peak and 27.23 sen/kWh off-peak; LV ToU charges 28.52 and 24.43 sen/kWh. Both our example buildings are on General tariffs, so each has one energy rate for every hour.
Step 3: The capacity and network charges pay for your peak
The capacity charge pays for generating capacity kept ready for your highest demand. The network charge pays for the transformers and cables that deliver it. As Part 14 explained, that equipment has to be sized for the peak, not the average. How these two charges are billed depends on your supply voltage.
On an MV tariff, they are charged per kW of maximum demand. On MV General, the capacity charge is RM29.43/kW and the network charge RM59.84/kW, RM89.27/kW together. On MV General, maximum demand counts at any hour of any day: the highest half hour of the month sets the charge, whenever it happens.
For our example office tower, the highest half hour was 2:30pm to 3:00pm on a hot weekday, at 1,600 kW:
Capacity: 1,600 kW × RM29.43 = RM47,088
Network: 1,600 kW × RM59.84 = RM95,744
Together that is RM142,832, nearly half of the office tower's bill, set by a single half hour. If the tower had kept its highest half hour to 1,500 kW, these two lines would have been 100 × RM89.27 = RM8,927 lower. Cobler's maximum demand charge guide goes into more detail.
On the MV ToU tariff the rates are RM30.19/kW (capacity) and RM66.87/kW (network), RM97.06/kW together. The difference is which half hours count: only demand inside the weekday 2pm to 10pm peak window is charged. A spike at 11pm, or on a Saturday, does not set the charge on MV ToU, although it would on MV General.
On an LV tariff, they are charged per kWh instead. Both LV General and LV ToU charge capacity at 8.83 sen/kWh and network at 14.82 sen/kWh. For our example shoplot:
Capacity: 8,000 kWh × 8.83 sen = RM706.40
Network: 8,000 kWh × 14.82 sen = RM1,185.60
This is why the shoplot's bill has no per-kW charge. The shoplot still has a busiest half hour in the month, and that peak still loads TNB's network. But the LV tariff recovers the cost of capacity and network through each kWh, so the bill has no maximum demand line. For the shoplot, these two lines go down only when its kWh go down. Lowering its peak alone does not change them.
Step 4: The retail charge is a fixed monthly fee
The retail charge is a flat fee for having an account. It does not depend on any meter reading.
MV: RM200 a month (our example office tower).
LV: RM20 a month (our example shoplot).
Step 5: The AFA changes every month
The Automatic Fuel Adjustment (AFA) adjusts the bill for the actual cost of the fuel used to generate electricity. It is a rate in sen/kWh that is set each month. It can be a surcharge (added) or a rebate (taken off). So always check which month an AFA figure belongs to.
For September 2026, the AFA is a surcharge of +3.67 sen/kWh. It is multiplied by your kWh:
Office tower: 500,000 kWh × 3.67 sen = 1,835,000 sen = RM18,350
Shoplot: 8,000 kWh × 3.67 sen = 29,360 sen = RM293.60
In another month, the same kWh could give a different AFA line. Cobler's AFA explainer tracks the monthly rates.
Step 6: A power factor surcharge is added only if the power factor is low
TNB sets a minimum power factor: 0.85 for supply below 132 kV and 0.90 for supply at 132 kV and above. As Part 9 explained, a low power factor means more current flows through the network for the same useful power. If a site's power factor is below the minimum, a surcharge is added to the bill. The exact calculation is set out in TNB's supply terms; check the current terms before estimating one. See Cobler's power factor surcharge guide.
Our example office tower runs at about 0.92, thanks to its capacitor banks, which is above 0.85. So its bill has no power factor surcharge. Our example shoplot's September bill has no power factor line either. Part 21 explains how capacitor banks raise the power factor.
Step 7: KWTBB and tax come after the main charges
KWTBB stands for Kumpulan Wang Tenaga Boleh Baharu, the Renewable Energy Fund. The levy is collected on the TNB bill and pays for renewable energy programmes. It is not based on a meter reading of its own. Your bill shows the KWTBB rate and the amount it is charged on. Check both on your current bill, because we have not confirmed them for this lesson, so our worked examples stop before KWTBB. Cobler's KWTBB guide explains who pays it and when it is waived.
Tax may also appear, depending on the account. Our worked examples stop before tax as well.
Step 8: Putting both bills together
Here are the two September 2026 bills side by side, before KWTBB and tax.
Bill line
Example office tower (MV General)
Example shoplot (LV General)
Energy
500,000 kWh × 29.83 sen = RM149,150.00
8,000 kWh × 27.03 sen = RM2,162.40
Capacity
1,600 kW × RM29.43 = RM47,088.00
8,000 kWh × 8.83 sen = RM706.40
Network
1,600 kW × RM59.84 = RM95,744.00
8,000 kWh × 14.82 sen = RM1,185.60
Retail
RM200.00
RM20.00
AFA (September 2026)
500,000 kWh × 3.67 sen = RM18,350.00
8,000 kWh × 3.67 sen = RM293.60
Power factor surcharge
None (PF 0.92)
None
Total before KWTBB and tax
RM310,532.00
RM4,368.00
Dividing each total by the kWh gives the average cost of one kWh:
The two bills respond to different things. For the office tower, nearly half the bill comes from the maximum demand, so one busy half hour matters a great deal. For the shoplot, every line except the RM20 retail charge follows its kWh, so using less energy is what lowers the bill.
What comes next: power electronics
This part completes the module on the grid, the meter and the bill. The next module looks at what happens to electricity inside modern equipment. Many devices, from phone chargers to variable speed drives, first convert AC to DC and sometimes back again. The next part, Rectifiers and Inverters, explains how.
Check your understanding
Why does our example shoplot's bill have no per-kW charge, when the office tower's does? The shoplot is on an LV tariff, which charges capacity and network per kWh (8.83 and 14.82 sen/kWh). The office tower is on an MV tariff, which charges them per kW of maximum demand (RM29.43 and RM59.84 per kW on MV General). The shoplot still has a peak, but its bill does not price it separately.
An MV building's highest half hour of the month happens at 11pm on a Saturday. Does it set the capacity and network charges? On MV General, yes: maximum demand counts at any hour. On MV ToU, no: only demand in the 2pm to 10pm weekday peak window is charged, so the highest half hour inside that window sets the charge instead.
Recap: A non-domestic TNB bill under RP4 has five main lines. The energy charge is kWh × a sen/kWh rate (split into peak and off-peak on ToU, with the peak window 2pm to 10pm on weekdays). Capacity and network charges are per kW of maximum demand on MV tariffs (RM89.27/kW together on MV General, counted at any hour; RM97.06/kW on MV ToU, peak window only) and per kWh on LV tariffs. The retail charge is fixed. The AFA is kWh × a rate that changes monthly (+3.67 sen/kWh in September 2026). A power factor surcharge is added only below the minimum, and KWTBB and tax come last. Our example office tower's September 2026 bill comes to RM310,532 before KWTBB and tax; our example shoplot's comes to RM4,368.
Cobler builds CobiNeural, a platform that shows a facility team its building's electricity as live numbers: energy, demand and power quality across the whole site. To see how your building uses electricity, talk to us.
Tan Kok XinElectricity Fundamentals
