The United States does not have one national residential net-metering policy. A rooftop solar customer's export rate, billing method, system-size limit, credit rollover, true-up, and eligibility depend on state policy, utility territory, regulator decisions, and the tariff in effect when the system interconnects.
Two homes in the same state can sometimes face different rules because one is served by an investor-owned utility while another uses a municipal utility or electric cooperative.
Net metering versus net billing
Under traditional net metering, exported kilowatt-hours offset imported kilowatt-hours according to the tariff's billing interval and credit rules. The credit may be close to the retail energy rate, but fixed charges and non-bypassable charges can remain.
Under net billing, imports and exports are valued separately. The customer pays the applicable retail rate for grid electricity and receives a different export credit, often based on avoided cost, wholesale value, time of export, or a regulator-approved methodology.
The global mechanics are explained in Export Tariffs, Net Metering, and Feed-In Tariffs. This page focuses on the fragmented US implementation.
Who sets the rules?
State legislatures may establish policy and delegate details to public utility commissions. Regulators approve investor-owned utility tariffs. Municipal utilities and electric cooperatives may have separate authority or exemptions.
Federal law affects parts of wholesale electricity and qualifying-facility policy, but ordinary residential retail rates and behind-the-meter solar compensation are largely matters of state and local utility jurisdiction.
The serving utility's current tariff and interconnection documents are the final operational sources for a specific home.
Retail-rate credit is not universal
The phrase net metering is sometimes used loosely to imply a one-for-one retail credit. Actual programs may exclude delivery charges, apply non-bypassable fees, use time-of-use values, limit annual surplus payments, or compensate net excess generation at a lower rate.
New customers may receive different treatment from legacy customers. A state can close one tariff while allowing existing systems to remain under prior terms for a defined period.
Ask for the exact tariff name, version, eligibility date, and legacy period.
Billing intervals matter
Some tariffs net imports and exports within each meter interval, while others use hourly, monthly, or annual accounting. Shorter intervals can reduce the amount of export that offsets imports directly.
Imagine a home exports 3 kWh in the afternoon and imports 3 kWh in the evening. Monthly netting might offset those quantities before certain charges. Interval net billing may credit the afternoon export at one rate and charge the evening import at another.
Savings models must reflect the actual interval rather than annual totals alone.
Credit rollover and annual true-up
Unused credits may roll into later months, expire, reset at an annual true-up, or receive a different cash-out value. Some tariffs do not issue cash refunds.
The true-up date can affect how seasonal surplus is carried. A household with strong summer production and winter consumption should understand which credits survive and at what value.
Ask what happens to unused monetary credits and unused kilowatt-hour credits separately.
System-size limits
Programs may cap eligible capacity by a fixed kW limit, historic annual usage, expected consumption, service size, or a percentage of load. Oversizing for future electric vehicles or heat pumps may require evidence or receive different export treatment.
A system can be technically approved for interconnection without qualifying for the most favorable compensation program. Confirm both decisions.
Export limits and hosting capacity
Utilities may limit export power because of transformer, feeder, voltage, protection, or hosting-capacity constraints. An approved system may need a smaller inverter, fixed export cap, certified control, operating schedule, or non-export configuration.
Non-export solar can still reduce onsite consumption, but production may be curtailed when the home and battery cannot absorb it. Model expected curtailment before accepting the design.
Time-of-use export rates
Some net-billing tariffs vary export value by hour, season, or grid condition. Midday exports may receive relatively little while late-afternoon or evening exports receive more.
This changes the value of west-facing panels, batteries, smart controls, and load shifting. A battery may store midday solar for household use or later export, subject to tariff rules.
Do not assume a high peak export price applies to every exported kilowatt-hour.
Fixed charges and minimum bills
Solar customers generally remain connected to and supported by the grid. Utilities may apply customer charges, minimum bills, grid-access charges, demand charges, or non-bypassable program costs.
These charges can remain even if annual solar production equals annual consumption. A salesperson promising a zero bill should identify every fixed and unavoidable charge.
Interconnection is separate from compensation
Interconnection approval confirms that the system may connect and operate under utility requirements. The export tariff determines billing treatment. Permitting confirms compliance with local building and electrical requirements.
One approval does not replace the others. Do not operate or export before receiving utility permission to operate where required.
Utility ownership types
Investor-owned utilities are generally regulated by state commissions. Publicly owned municipal utilities answer to local governing structures. Electric cooperatives are member-owned and may be regulated differently by state.
This structure explains why a statewide summary may not match the homeowner's provider. Search by utility name and service address, not state alone.
Community solar uses different billing
Community solar subscribers typically receive bill credits allocated from an offsite project. Credit rates, subscription charges, escalation, cancellation, and low-income benefits are program-specific.
Community solar is not ordinary rooftop net metering. Review the subscriber agreement and utility tariff together.
What to request from an installer
Before signing, ask for:
- Serving utility and exact tariff.
- Import rates and export-credit method.
- Required time-of-use plan.
- Fixed and non-bypassable charges.
- Billing interval and true-up rules.
- Credit rollover and expiration.
- System-size and export limits.
- Legacy period or future tariff risk.
- Interconnection fees and upgrade exposure.
- Savings model using current tariff data.
The quote should state the date on which rates were retrieved.
How to verify the current rule
Start with the serving utility's distributed-generation page and tariff. Check the state public utility commission and current legislation. Use DSIRE as a discovery database, then confirm details through the authority that administers the rule.
Save the tariff and application materials used for the project. Utility webpages can change after the system is installed.
For California investor-owned utilities, see the separate California NEM 3.0 Reader Guide. For rate timing, continue to US Time-of-Use Rates and Solar Savings.