Net Metering Explained: How Solar Credits, Banking, and True-Ups Work

Here's the paradox net metering was designed to solve: solar panels produce their peak power at midday, when most homes are empty — and almost nothing in the evening, when household usage spikes. Without a way to bridge that gap, much of a system's output would go to waste. Net metering is the billing arrangement that bridges it. When your panels produce more than your home is consuming, the surplus flows to the grid and you earn credits; when production falls short, you draw power back and spend them. For how the equipment itself turns sunlight into usable electricity, see our guide to how solar panels work.

What Net Metering Actually Is

At its simplest, net metering means your monthly bill is based on the net difference between two flows: the electricity you exported to the grid and the electricity you imported from it. Say your panels send 900 kWh to the grid this month while your house pulls 900 kWh back after dark — under a straightforward net-metering tariff, those cancel out and you owe little more than fixed charges. The netting usually happens over each billing cycle, with unused credits rolling forward, which is what turns the grid into a kind of battery for your solar production.

How the Bidirectional Meter Works

The mechanical heart of the arrangement is a meter that tracks power moving both ways:

What Happens to Excess Solar Power

Every surplus kilowatt-hour earns a credit. Under traditional retail-rate net metering, that credit is typically one kWh of bill offset per kWh exported — effectively valued near the retail rate you would otherwise pay, though exactly which rate components count depends on the tariff.

Those credits bank on your account and roll month to month. That matters seasonally: in many climates a system overproduces in mild months and draws credits down during peak air-conditioning or winter stretches. Then comes the true-up — most tariffs settle the account once a year. If you still hold excess credits at true-up, the utility generally pays them out at a much lower rate, commonly tied to avoided cost (the utility's cost of generating or buying equivalent power, often just a few cents per kWh). Because of that gap, well-designed systems are usually sized to cover your consumption rather than to pile up annual surpluses.

Retail Rate vs. Avoided Cost: The Core Distinction

The single most important number in any net metering conversation is what one exported kWh is worth on your bill:

Retail rates bundle energy, grid delivery, and various charges; avoided cost strips it down to the bare energy value. That's why a retail-rate credit can be worth several times an avoided-cost payment for the identical electron — a multiple that varies by market and is best treated as an estimate, since rates change.

Net Billing and Other Variants

"Net metering" is really a family of designs:

• Net billing: exports are valued instantly at a set (usually lower) rate, while imports stay billed at retail. Your solar kWh is worth the most when you use it yourself.
• Time-of-use export credits: export value shifts by hour, rewarding late-afternoon exports and penalizing midday surplus — one driver of battery add-ons.
• Caps and waitlists: some utilities limit total enrolled solar capacity or pause new enrollments once thresholds are reached.
• Fixed charges and minimum bills: grid-access or minimum-bill provisions can trim the value of any export arrangement.

Why Policy Details Vary So Much

There is no single national net metering law in the United States. Export rules are set state by state — typically by public utility commissions implementing legislation — and utility by utility. Investor-owned utilities usually fall under state mandates, while cooperatives and municipal utilities are often exempt and may offer weaker terms or none at all. The same state can therefore contain sharply different deals depending on who sends your bill.

What's Changed for New Solar Customers in Recent Years

The trend line matters if you're going solar now. Several large solar markets have replaced retail-rate net metering for new customers with lower-value export schemes — most prominently California, which moved new customers to a net billing tariff in 2023 with much lower, time-of-day-varying credits (a shift commonly reported to have cut export value by well over half), and Hawaii, which made a comparable move years earlier. Other states have run reviews, capacity caps, or successor-tariff debates with varying outcomes.

Meanwhile, plenty of utilities still offer classic retail-rate net metering to new customers. In Florida, for example, the major investor-owned utilities have continued retail-rate net metering in recent years despite repeated legislative attempts to phase it out — see our worked example of how FPL net metering credits show up on a real Florida bill. Where programs do change, customers who interconnected under the old tariff are usually grandfathered for a defined period, commonly cited as a decade or more — one reason the timing of your interconnection can genuinely change 20-year economics.

What Net Metering Means for Your Payback

Export credits are a pillar of solar savings math. When they're valued at retail, payback periods tend to shorten and modest oversizing is more forgiving; when they drop to avoided cost, self-consumption and batteries become the value story instead. Either way, the honest approach is to model your own usage, rates, and local tariff rather than rely on generic averages — start with our solar ROI calculator, and pair it with the basics in how solar panels work to understand what your roof can actually produce.