What Is Net Metering? How It Works & Saves Money

The short answer

Net metering is a billing arrangement that lets your solar system use the grid as a battery. When your panels produce more electricity than your home is using, the surplus flows out to the grid and your utility records it as credits. When you later pull power from the grid — at night, on cloudy days — those credits offset what you owe. At the end of the billing period you pay only for your net consumption: what you took, minus what you gave. That simple idea is the reason a solar system can cover nearly 100% of a household's annual electricity bill even though the sun only shines during the day. (Policy details differ by country — see our country guides to net metering vs net billing in Pakistan and net metering with Meralco in the Philippines.)

How net metering actually works, step by step

Everything hinges on one piece of hardware: the bi-directional meter. A standard electricity meter only measures power flowing one way — into your home. When you install solar under a net-metering program, your utility installs a meter that separately tracks two flows: electricity imported from the grid and electricity exported to it.

Here is a typical day for a net-metered home:

Midday — surplus. Your 6 kW array is producing, say, 5 kW, but the house is only using 1 kW (fridge, a few lights, standby loads). The other 4 kW flows out to the grid, and the bi-directional meter logs those kilowatt-hours as credits on your account.

Evening — deficit. The sun sets. The house draws 3 kW for cooking, lights, and the TV, all from the grid. Instead of charging you the full retail rate for those kWh, the utility first draws down the credits you banked at midday.

Month end — settlement. The utility totals your imports and your exports. If you imported 800 kWh and exported 700 kWh, you pay for 100 kWh. If you exported more than you imported — a surplus month — the excess usually carries forward as a credit (the rules on rollover and on what happens to year-end surpluses are called the true-up, covered below).

Note that credits are denominated in kilowatt-hours, not money, under classic net metering. A kWh you export cancels a kWh you import, regardless of when each flow happened. That is why net metering is sometimes called one-for-one crediting.

One more hardware detail: on older systems the "bi-directional meter" was literally the same spinning-disc meter running backward, which is where the word net comes from — the meter showed the net of your consumption. Modern installs use a digital meter with separate import and export registers, which lets the utility apply different rates to each flow. That distinction is also why net billing is technically possible on the same meter — the meter can tell exactly which kWh went which way, and the billing software prices them separately.

The true-up: where credits get settled

The true-up is the accounting moment when your utility reconciles everything. Most utilities true up monthly, some annually, and the details matter more than most installers admit:

Credit rollover. Many programs let unused kWh credits roll into the next month, which is what lets summer surpluses offset winter deficits. Others cap the rollover or expire credits after 12 months.

Year-end surpluses. If your annual true-up shows a net surplus — you exported more than you imported all year — utilities handle it differently: some zero it out, some pay a small wholesale-rate buyout, some let it roll indefinitely. This is why oversizing a system "just in case" can be a money-loser in some territories: surplus kWh at the true-up may be worth nothing.

Fixed charges. Net metering credits offset the energy portion of your bill. The utility's fixed monthly connection charge, and in some areas demand charges or grid fees, usually still apply — so a net-zero-energy home can still have a small nonzero bill. Some utilities also charge solar customers a minimum monthly fee. Always read the tariff, not the brochure.

Demand charges. A few utilities bill some customers partly on their peak demand rather than total energy. Net metering rarely offsets demand charges, because your peak draw usually still comes from the grid after sunset. This matters less for homes than for businesses, but it is another line on the bill that export credits typically do not touch.

Net metering vs net billing vs feed-in tariff

Three terms get tangled constantly, and they describe genuinely different money flows:

Scheme	How exports are valued	Credits denominated in	Effect on your bill
Net metering	Exported kWh offsets imported kWh one-for-one, at the retail rate	Kilowatt-hours	You pay for net consumption only; a kWh out cancels a kWh in
Net billing	Exports credited at a defined export rate, usually below retail	Money (or kWh converted at the export rate)	Imports billed at retail, exports credited separately at the lower rate
Feed-in tariff (FiT)	All generation paid a fixed rate per kWh, often under a long contract	Money	You get paid for what you generate — sometimes on top of avoiding imports

The practical difference: under one-for-one net metering, self-consumed and exported kWh are worth the same, so a smaller system that covers your bill can be optimal. Under net billing, exported kWh are worth less than self-consumed kWh, so the economics shift toward using your own power directly — running the washing machine at midday, heating water at noon — and toward batteries that let you shift cheap solar into expensive evening hours.

Why your utility's policy is not like your neighbor state's

In the United States there is no single national net-metering policy. Rules are set at the state level — and often differ within a state between investor-owned utilities, municipal utilities, and rural cooperatives. That means two homes 20 miles apart can face completely different economics:

Crediting ratio. Some utilities still offer one-for-one retail crediting. Others credit exports at an avoided-cost or wholesale-style rate that can be a fraction of the retail price.

System-size caps. Many programs cap eligible system size — commonly at some percentage of your historical usage or at a fixed kW ceiling — so you cannot build a commercial-scale array on a residential account.

Fees and demand charges. Some utilities add monthly solar fees, higher fixed charges, or demand-based charges that blunt the savings from exported power.

Grandfathering. When utilities revise their tariffs — and they do, regularly — existing customers are often grandfathered into the old rules for a fixed number of years. That makes when you interconnect a real variable in the payback math.

Before you size a system, pull your own utility's current distributed-generation tariff and read it yourself. Installer savings quotes sometimes assume the most generous interpretation of the rules; the tariff is the document your actual bill is calculated from.

The global trend: toward net billing

One-for-one net metering was the policy that launched residential solar in dozens of countries — but in many markets the trend has been toward net billing or hybrid schemes. The argument utilities make is that full retail crediting lets solar owners use the grid for free while non-solar customers absorb the grid's fixed costs. Regulators in several regions have agreed, at least partly, and restructured export compensation downward.

For solar shoppers, the takeaway is directional rather than alarming: export compensation is getting less generous over time, while self-consumption is getting more valuable. That means the systems with the strongest economics today are the ones designed to use their own power — well-matched array sizing, daytime load shifting, and where it pencils out, a battery to ride through the evening peak. Countries that moved away from one-for-one crediting illustrate the mechanics clearly — our Pakistan net metering vs net billing guide walks through exactly how that shift changes the math, and the Philippines/Meralco guide shows how one country's export-rate rules work in practice.

Who benefits most from net metering?

Homes with generous one-for-one crediting. This is the obvious one — every exported kWh is worth full retail, so the system behaves like a perfect battery.

Empty-daytime homes. Households where everyone is out during peak sun hours export a large share of generation. Under one-for-one crediting those exports return full value at night; under net billing, they return less — which is exactly why daytime usage patterns matter more under newer tariffs.

Oversized arrays (under generous rules). A system sized above your consumption banks summer surpluses against winter deficits. But check your utility's true-up treatment of year-end surplus first — if excess is zeroed or bought at a token rate, the extra panels were a donation.

High-rate households. Every kWh you offset is worth the retail rate you avoided, so the higher your utility's per-kWh price, the faster the payback — regardless of the crediting scheme.

The honest version: net metering is a fantastic deal where it exists in its classic form, a decent deal under net billing if you self-consume, and a trap only if you size for exports nobody will pay for. Run your own numbers in the solar cost calculator with your utility's actual export rate plugged in — that one input changes the payback more than panel brand, tilt, or anything else on the roof.