MyPinoyTools

Methodology

Maintained by the MyPinoyTools Team · Last reviewed 2026-07-18

The exact formulas, rate sources, and validation behind our calculators: per-component charges, monthly VAT rates, distribution brackets, and the real bills we check every result against.

Our rule is simple: every number on this site is either computed from a published rate schedule or checked against a real bill, and anything we cannot source is marked as unverified rather than presented as fact. This page is where you check our work.

How we compute a Meralco bill

A Meralco residential bill is not one rate times your kWh. It is a set of separate charges, each computed on its own basis, then taxed on its own terms. We reproduce that sequence exactly:

  1. Compute each rate component and round it to the centavo. Per-kWh charges are consumption × rate; fixed charges are billed per month. Rounding happens per line, because the section totals printed on a real bill are sums of already-rounded lines.
  2. Apply the local franchise tax. 0.5% of the pre-VAT total of generation, transmission, system loss, distribution, senior citizen and real property tax. Universal charges, FiT-All, GEA-All, lifeline and the energy tax are excluded from this base.
  3. Apply VAT per component, at that month's effective rates. Not a flat 12%. See the table below.
  4. Add the untaxed charges (universal charges, FiT-All, GEA-All and lifeline) to reach the Total Energy Amount, which is the figure our calculator targets.

Account-specific items on a real bill sit outside this calculation: bill deposits, applied credits, arrears. No calculator can predict them, so we take them as an optional input instead of guessing.

Two different tiering mechanisms

The same rate schedule contains two opposite mechanisms, and conflating them is the most common way to get a bill wrong.

Distribution: whole-consumption re-rating

The residential distribution charge is bracketed by consumption, and the bracket you land in re-rates all of your kWh. It is not marginal. A 368 kWh bill is charged 368 × the 301–400 rate, which is how real bills print it.

Distribution charge brackets, July 2026 billing
Monthly consumptionRate applied to every kWh
0–200 kWh₱0.9803 / kWh
201–300 kWh₱1.2908 / kWh
301–400 kWh₱1.5837 / kWh
Over 400 kWh₱2.0941 / kWh

Energy tax: marginal brackets

The energy tax under Batas Pambansa Blg. 36 works the opposite way: each bracket's kWh are charged at that bracket's rate, and the first 650 kWh are free. Most households never see this line.

VAT is not a flat 12%

Portions of the pass-through charges are zero-rated, so the effective VAT rate differs per component and changes every month. These are the rates for July 2026 billing:

Effective VAT rate per charge, July 2026 billing
ChargeEffective VAT
Generation10.05%
Transmission10.29%
System Loss10.08%
Distribution (Meralco)12%
Senior Citizen12%

Lifeline, real property tax, local franchise tax, universal charges, FiT-All, GEA-All and the energy tax carry no VAT.

Current rates (July 2026 billing)

These are the exact figures our calculators use, read directly from our rate file. Last updated 2026-07-18.

Meralco residential rate components, July 2026 billing
ComponentRate
Generation Charge (PhP/kWh)₱9.2504 / kWh
Power Act Reduction₱0.0000 / kWh
Transmission Charge(PhP/kWh)₱1.2786 / kWh
System Loss Charge (PhP/kWh)₱0.8751 / kWh
Metering Charge per kWh₱0.3350 / kWh
Supply Charge per kWh₱0.4979 / kWh
AWAT(Refund)/Collect(PhP/kWh)₱-0.4278 / kWh
Regulatory Reset Fee Adj₱-0.0023 / kWh
Senior Citizen Subsidy₱0.0001 / kWh
RPT Charge (PhP/kWh)₱0.0065 / kWh
Missionary Elec for NPC-SPUG₱0.2662 / kWh
Missionary Elec for REDCI₱0.0101 / kWh
Environmental Fund₱0.0025 / kWh
NPC Stranded Contract Costs₱0.0000 / kWh
NPC Stranded Debts₱0.0428 / kWh
DU Stranded Contract Costs₱0.0000 / kWh
Equalization Taxes & Royalties₱0.0000 / kWh
FiT-All (Renewable)₱0.2011 / kWh
GEA-All (Renewable)₱0.0000 / kWh
Lifeline Subsidy Rate (PhP/kWh)₱0.0100 / kWh
Fixed Metering Charge (PhP/mo)₱5.00 / month
Fixed Supply Charge (PhP/mo)₱16.38 / month

Things that are easy to get wrong

The local franchise tax varies by city

The official schedule states that this rate is set per local government unit. Across the bills we hold it differs by city in the same month: 0.50% in one, 0.55% in another. Our calculator defaults to 0.5% and states that assumption on screen, because we cannot know your city from your bill total alone. If your bill's LFT Charge line shows a different percentage, that is the one that applies to you.

“Lifeline” means two different things

The lifeline subsidy rate is a charge, currently ₱0.0100 per kWh, paid by customers who are not lifeline beneficiaries to fund the programme. The lifeline discount is a reduction received by qualified households, at 100% below 50 kWh, 35% for 51–70 kWh, and 20% for 71–100 kWh.

These are separate mechanisms, and low consumption alone does not earn the discount. One of our validation bills used 87 kWh, squarely inside the 20% band, and was billed at full rates while still paying the subsidy charge, because the discount under Republic Act 11552 goes to registered qualified end-users. For that reason our calculator never applies a lifeline discount automatically from consumption, and we have not yet been able to validate the discount path against a bill from a registered household.

GEA-All is currently ₱0.0000

The Green Energy Auction charge appears on bills at zero because the Energy Regulatory Commission suspended collection through the August 2026 billing period, per its announcement of 29 June 2026. When charged, the rate on our validation bills was ₱0.0371 per kWh. The suspension has been extended twice on a two-month basis and is expected to be reviewed again, so we re-check it with every monthly rate update.

Appliance estimates

Appliance consumption is watts ÷ 1,000 × hours per day × days per week ÷ 7, multiplied by 30 for a monthly figure. For compressor-driven appliances we multiply by a duty cycle, the average fraction of rated wattage actually drawn, because a compressor cycles on and off rather than running continuously. Inverter models are modelled with a lower duty cycle, not a lower rated wattage.

Costs use the all-in effective rate per kWh derived from the current rate schedule. That is an average rate across the whole bill, not a marginal rate, and it is stated on screen.

Status: provisional. The 51 preset wattages and their duty-cycle factors are engineering estimates for typical Philippine models, last reviewed 2026-07-18. We are verifying them against manufacturer and Department of Energy references; any preset we cannot source will be corrected or removed. Duty-cycle factors are the least certain figures on this site.

How we validate

We test against real Meralco bills, transcribed line by line. A bill does not pass because the total looks close. It passes only when every printed figure on it matches ours to the centavo: each of the roughly 30 charge lines, every section subtotal, every printed percentage share, and the final Total Energy Amount. Across the set that is 484 individual figures, and every one of them matches.

What matters more than how many bills we hold is what they cover. A Meralco bill changes shape with consumption, with the city you live in, with the month, and with whichever layout Meralco was printing at the time. Each of those is somewhere the arithmetic can go wrong, so each is deliberately represented:

What our validation set covers
What we testedCovered
Every consumption bracket44 kWh in the lifeline band up to 950 kWh, crossing all four distribution brackets and the energy-tax threshold
Separate households6 different accounts, not one household's bills repeated
Different cities2 localities that charge different local franchise tax rates, so the tax structure itself is tested, not just one city's
Different rate months5 monthly schedules, covering generation, transmission and VAT rates that move every month
Different bill layouts3 formats Meralco has used, including a transitional one that groups charges the old way but taxes them the new way
Independent checks4 bills whose rates came from a different source than the bill itself, and still matched exactly

Those independent checks are the strongest evidence here. In one, the rates came from Meralco's own published schedule; in the other, from a different household's bills in the same month. Both times the engine reproduced a bill its rate data had never seen. That is the difference between being correct and merely being self-consistent.

For transparency, that coverage currently comes from 9 transcribed bills. We would rather hold a handful spread across every bracket, city and format than a hundred from a single household, because a hundred near-identical bills would test the same arithmetic a hundred times.

What we have not validated: the lifeline discount path, for want of a bill from a registered lifeline household; bills with a meter multiplier other than one; and any utility other than Meralco.

Sources

Changelog

Found something wrong? We would rather fix it than defend it. Corrections to any figure on this page are welcome, and we will note the change here.