Net metering is a billing arrangement between a solar-powered home and its utility: when panels produce more electricity than the home is using, the surplus flows onto the grid and the customer receives a credit; when the panels aren’t producing enough, the home draws power from the grid as usual and the credit offsets that draw. The exact value of that credit, how it’s calculated, and whether it rolls over month to month all depend on the specific program a utility or state/province has adopted — there is no single national standard.
The idea sounds simple, and at a conceptual level it is. The details — what a unit of exported solar electricity is actually worth, how often the account is reconciled, and what happens to unused credits — are where net metering programs differ sharply from one utility territory to the next, and where a homeowner comparing quotes needs to ask specific questions rather than assume.
The basic mechanics
A home with solar panels is still connected to the grid in almost every residential case. During sunny hours, the panels may generate more electricity than the household is consuming at that moment. Instead of that excess going to waste, it’s exported through the same meter connection that normally brings power in. A bidirectional meter (or two separate registers) tracks both directions of flow.
At the end of a billing cycle, the utility compares how much the home pulled from the grid against how much it pushed out. If the two amounts are equal, the account nets to zero for that period, aside from any fixed charges. If the home exported more than it imported, the surplus becomes a credit; if it imported more, the customer pays for the difference in the usual way.
How solar panels generate that electricity in the first place — converting sunlight into direct current that’s then converted to usable alternating current — is covered in more detail in how solar panels actually work, which is worth understanding before evaluating any net metering offer.
Why the credit’s value isn’t fixed
The single biggest source of confusion around net metering is assuming that exported electricity is worth the same as electricity purchased from the grid. In many programs it is not. Some jurisdictions credit exports at the full retail rate, meaning a kilowatt-hour sent out is worth the same as a kilowatt-hour bought back later. Others credit exports at a lower “avoided cost” or wholesale-type rate, which is typically less than the retail price. Some newer program designs replace one-to-one crediting entirely with more complex, time-varying export rates.
Because this determines a large part of what solar ownership actually delivers financially, it is not something a general article can state as a number — the applicable rate is set by state or provincial regulators, utility commissions, or individual utility tariffs, and it changes as those bodies revisit policy. The only reliable way to know the current export rate for a specific address is to check with the utility or the relevant public utility commission directly.
Rollover, expiration, and cash-out rules
Most net metering programs don’t settle accounts every month in isolation. Instead, credits typically accumulate over an annual cycle, so summer surpluses can offset winter shortfalls when a home’s solar production is much lower. What happens at the end of that annual cycle varies:
- Some utilities let unused credits carry forward indefinitely.
- Some zero out or expire credits at the end of the annual true-up period.
- Some pay out remaining credits in cash, often at a rate lower than retail.
- Some cap how much credit a single customer can accumulate.
These rules are set at the program level, not chosen by the homeowner, and they can change when a program is redesigned. A household evaluating solar should find out not just today’s rate but whether the program is a “grandfathered” one — some jurisdictions let existing solar customers keep old terms for a set number of years even after new terms take effect for new applicants — which is a detail worth confirming directly with the utility before signing anything.
Net metering vs. net billing vs. buy-all/sell-all
Because terminology gets used loosely, it helps to separate three structures that get lumped together as “net metering”:
| Structure | How it generally works |
|---|---|
| Traditional net metering | Exported and imported electricity are credited/charged at the same or a closely tied rate; often one-to-one. |
| Net billing | Exports are credited at a separate, usually lower, rate than imports; the two are tracked but not treated as equivalent. |
| Buy-all/sell-all | All solar production is sold to the utility at one rate, and all household consumption is bought back at another; the two are billed independently rather than netted. |
A given utility may use any of these, may be transitioning between them, or may apply different structures depending on system size or when the customer applied. This is a case where the label a salesperson uses (“net metering”) may not match the structure actually in place — it’s worth asking which of these three is being described.
What determines eligibility and system sizing
Not every home or every system size automatically qualifies. Utilities commonly set rules around:
- System capacity limits — a cap relative to the home’s historical electricity use, meant to discourage oversized systems built purely to export.
- Interconnection approval — a technical review and application process before the system can be connected and start earning credits.
- Program caps — some utilities cap total enrolled solar capacity across their whole service territory and stop accepting new net metering applicants once that cap is reached, sometimes moving new applicants to a different, less favorable tariff.
- Battery pairing rules — adding a home battery alongside solar can change how a system is metered in some programs, since stored energy discharged later can blur what counts as “excess.”
These variables are why two neighboring homes on different utilities — or even the same utility a year apart — can end up with meaningfully different arrangements for what looks like an identical rooftop system.
Where net metering fits with other incentives
Net metering is a billing mechanism, not a subsidy, but it’s often discussed alongside actual incentive programs like tax credits, rebates, and performance-based payments. Those are separate policies with their own eligibility rules, application deadlines, and funding limits, covered in more general terms in how solar tax credits and rebates work. It’s also worth knowing that not every home suited to solar has to own a rooftop system to benefit from similar crediting arrangements — community solar programs let subscribers receive bill credits from a shared off-site array under a comparable, though distinct, set of rules.
Because incentive programs and net metering tariffs are both set by policy bodies that revisit them periodically, the landscape a homeowner sees in a sales pitch may not match what’s actually available by the time a system is installed and interconnected months later. The Policy & Incentives section tracks how these kinds of programs generally function, and a household’s own utility or state/provincial energy office remains the authoritative source for what currently applies to a specific address.
Questions worth asking before relying on net metering
- Is the export credit rate the same as the retail rate, or lower — and is that rate fixed or does it change by time of day or season?
- Do unused annual credits roll over, expire, or get cashed out, and at what rate?
- Is the program open to new applicants, or has a capacity cap been reached in this territory?
- If policy changes after installation, would this system be grandfathered under current terms, and for how long?
- How does adding a battery affect metering, if that’s part of the plan?
Getting straight, current answers to these from the utility or program administrator — rather than from a sales quote — is the difference between understanding the arrangement and guessing at it. Related mechanical questions, like how the system connects to the home’s wiring and where it fits alongside rooftop versus ground-mount options, are also worth raising with anyone bidding on the installation, alongside the broader list in what to ask a solar installer before you sign.
Frequently asked questions about net metering
Is net metering the same everywhere in the US?
No. Net metering is set at the state or utility level, not federally, so credit rates, rollover rules, and system caps differ across states and even between utilities within the same state. Some states have no mandated net metering at all, relying instead on utility-specific tariffs.
What happens to unused solar credits at the end of the year?
It depends entirely on the program. Some utilities let credits roll over indefinitely, some zero them out at an annual true-up, and some pay out remaining credits in cash, often at a lower rate than retail. Check the specific tariff with the utility.
Does net metering still make sense if my utility switched to net billing?
Net billing typically credits exports at a lower rate than imports, which changes the economics compared with one-to-one net metering. Whether it still fits a household’s situation depends on usage patterns, system size, and the specific credit rate — details only the utility or a licensed local professional can confirm.
Can I lose net metering after I already have solar installed?
Many programs “grandfather” existing customers under the terms in place when they interconnected, for a set number of years, even after rules change for new applicants. Whether that protection applies, and for how long, is set by the specific program and should be confirmed before installation.
Do batteries affect how net metering works?
Yes, in some programs. Storing power in a home battery instead of exporting it immediately can change what counts as surplus for metering purposes under certain tariffs, so it’s worth asking the utility how battery pairing is treated before combining the two.
The Cleaner Energy publishes general information about clean energy technology, not financial, tax, legal or engineering advice. We are writers and editors, not installers, contractors or financial advisers. Incentives, rebates, utility rates and equipment costs vary by location and change over time — confirm current figures with the official program administrator, your utility, or a licensed local professional before making a purchase or installation decision.