Is plug-in solar legal in my state? US rules, limits and certification

Plug-in solar is a small solar kit that you plug into an ordinary wall outlet, so the power it makes goes straight to the things running in your home. In Europe it is often called balcony solar. In the US it is legal in some states, coming soon in others and not covered by any law in most, so the answer to "can I use it?" depends on where you live. This guide goes through the rules state by state as we found them on October 20, 2026.

The short version

• Plug-in solar is allowed and in force in six states: Utah, Colorado, Maine, Maryland, Vermont and Connecticut.
• Four more have signed laws that start later: Virginia, New Hampshire and California on January 1, 2027, and New Jersey on March 1, 2027.
• Eight states have a live bill. In Washington, DC we could not confirm the status from an official page. The other 32 states have no plug-in law.
• Most laws cap a kit at 1,200 watts (W) of output; Colorado allows 1,920 W. Some states have a lower limit for plugging in without wiring changes: 420 W in Maine, 391 W in Colorado, Maryland and Virginia, 400 W in New Jersey.
• The laws ask for a kit tested by a recognized lab. We go further: we only recommend a kit when UL 3700, the safety test written for plug-in solar, covers the kit or at least its microinverter.
• Some states ask you to tell your utility, and renters and HOA members have extra steps in some states.
• These rules change quickly. We re-check our state table at least every 90 days.

What plug-in solar is, in plain words

A plug-in kit has one or two solar panels, a microinverter and a cord with a plug. Panels make direct current (DC), the kind a battery gives. Your home runs on alternating current (AC), the kind that comes out of the wall. The microinverter is a small box that translates DC into AC. Our solar glossary explains these terms.

Watts (W) are how fast power flows, like how fast water leaves a tap. Kilowatt-hours (kWh) are how much energy you used, like the water in the bucket. Your bill charges for kWh, so the kit saves money when your home uses its power while the sun shines.

Every state law we read requires the kit to stop when the grid goes down, so it does not keep your lights on in an outage. For that, see our guide to backup power for outages.

Why the rules are patchy in the US

Electric rules are set mostly by states and utilities. Without a plug-in law, a device that sends power into your home's wiring falls under your utility's normal interconnection rules (the process and contract for connecting a generator to the grid), the same path used for rooftop solar. The new state laws create a short path for small kits: no utility approval, no fee and no extra equipment, as long as the kit meets the law's conditions. Utah's law has been in effect since May 7, 2025; most of the others passed in 2026.

States where plug-in solar is allowed and in force

We re-read these six laws on official state sites on October 20, 2026.

• Utah (HB 340, in force since May 7, 2025). Up to 1,200 W through a standard 120-volt outlet, meeting the current National Electrical Code (the national rulebook for wiring) and certified by UL or an equivalent nationally recognized testing laboratory (NRTL, a lab approved by the federal government to test products for safety). No utility approval, fee or extra equipment; not part of net metering (the program that credits you for power sent to the grid). The law binds "electrical corporations", the investor-owned utilities such as Rocky Mountain Power; a city utility or co-op may have its own rules.
• Colorado (HB26-1007, in force since August 12, 2026). One device per address, up to 1,920 W to the grid, labeled and listed by an NRTL, and no more than one device on a single wall outlet. Your utility may ask you to tell it about the device and its size. Devices up to 391 W are exempt from code or listing rules that would require wiring changes. From January 1, 2027, a device above 391 W may not be sold in Colorado unless it is UL labeled and listed.
• Maine (35-A M.R.S. section 3475, in force since July 29, 2026). You may plug in up to 420 W per service address yourself. From 420 W to 1,200 W, a Maine-licensed electrician must install it on a dedicated circuit with a single outlet, and you notify the utility within 30 days. Listed to UL 3700 or a comparable standard by an NRTL. No net energy billing.
• Maryland (HB 1532, Chapter 353, in force since May 12, 2026). One system per meter, residential only, up to 1,200 W, certified by an NRTL such as UL. Notify your electric company before installing, with a certification of the device's safety features and maximum output. Devices up to 391 W are exempt from listing rules that would require wiring or panel changes.
• Vermont (Act 149, in force since July 1, 2026). One or more devices per meter, up to 1,200 W combined, complying with UL 3700. Only homes with a smart meter qualify. Not allowed if you already have a net-metered solar system, and power sent to the grid is not paid for.
• Connecticut (Public Act 26-127, in force since October 1, 2026). One device behind a customer's meter, up to 1,200 W, through a 120-volt outlet, not permanently fixed to a building, certified by UL or an equivalent lab and meeting UL 1741 (a safety standard for inverters). Building, fire and local codes still apply.

States with a law that starts later

• Virginia, January 1, 2027: up to 1,200 W per customer, NRTL-certified, notice to the utility on the State Corporation Commission form before you install, and a 391 W limit for plugging in without wiring or panel changes.
• New Hampshire, January 1, 2027: one system per metered customer, up to 1,200 W, NRTL-certified; the utility may ask you to report its size.
• California, effective January 1, 2027; we are confirming the final text. SB 868 was signed on September 30, 2026. The official committee analysis describes devices up to 1,200 W per dwelling on a 120-volt outlet, NRTL-certified. We have not yet read the final text of the law as signed (the chaptered text), so treat these details as provisional until we do. We re-check it with the rest of our state table at least every 90 days.
• New Jersey, March 1, 2027: up to 1,200 W per service address (or per dwelling unit in multi-family housing), listed to UL 3700 or a comparable standard, with a 400 W limit for plugging in without wiring or panel changes.

Until those dates, the old rules apply.

States with a pending bill, an unclear status, or no law

Pending: Delaware, Illinois, Massachusetts, Michigan, New York, North Carolina, Ohio and Pennsylvania. New York's bill passed both houses on May 28, 2026 and has not yet been delivered to the governor. Massachusetts has had its bill in a conference committee (members of both chambers working out one version) since July 16, 2026.

Unclear: Washington, DC. Council bill B26-0602 is reported to include plug-in solar, but we could not read the Council's official page to confirm it. No plug-in law is in force there.

No plug-in law: Alabama, Alaska, Arizona, Arkansas, Florida, Georgia, Hawaii, Idaho, Indiana, Iowa, Kansas, Kentucky, Louisiana, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Mexico, North Dakota, Oklahoma, Oregon, Rhode Island, South Carolina, South Dakota, Tennessee, Texas, Washington, West Virginia, Wisconsin and Wyoming.

"No law" does not mean "banned". It means there is no short path, so your utility's normal interconnection rules apply. Ask your utility what it requires before you connect anything.

Power limits, and the lower "no electrician" limits

The 1,200 W cap is the kit's AC output, what the microinverter can push into the outlet, not the total wattage printed on the panels.

Some states add a lower number. In Maine, 420 W is the most you may plug in yourself. In Colorado, Maryland and Virginia, devices up to 391 W are exempt from code or listing rules that would require wiring changes; New Jersey's figure is 400 W. Above those sizes, the product's listing or the building code may call for a dedicated circuit, meaning one outlet with its own breaker in your breaker panel, the box of switches that protects your wiring. The laws do not explain how these numbers were chosen, and whether your own wiring suits a kit of any size is a question for an electrician.

An example from the Maine law: you rent an apartment in Portland, Maine and look at an 800 W kit. That is above 420 W, so the law requires a licensed electrician, a dedicated circuit with a single outlet and a notice to the utility within 30 days. A kit of 420 W or less avoids all three (our reading of the statute).

UL 3700 and what "certified" means

UL 3700 is the "Outline of Investigation for Interactive Plug-in Photovoltaic Equipment and Systems", as Maine's law names it. An outline of investigation is a lab's test document used before a full standard exists.

The laws word the certification rule differently:

• Vermont requires UL 3700.
• Maine and New Jersey require UL 3700 or a comparable standard from an NRTL.
• Connecticut names UL 1741, not UL 3700.
• Utah, Colorado, Maryland, Virginia, New Hampshire and California ask for certification by UL or another NRTL without naming one standard in the texts we read.

Our rule is stricter on purpose. We only recommend a kit in two cases:

1. Kit level: the kit as sold is certified to UL 3700, shown by the lab's public listing or the maker's certificate.
2. Parts level: the microinverter is certified to UL 3700, and the panels to UL 61730 or the older UL 1703 (the safety standards for solar panels; the California Energy Commission's public list shows which one each panel has). Then we say plainly that the parts are certified, not the kit as a whole.

On October 19, 2026, we found no kit certified to UL 3700 as a complete kit; a few qualify on the parts level. To check a claim, ask the seller for the lab and the certificate or listing number, and look it up in that lab's public directory. A logo alone is not proof.

Telling your utility

• Maryland: notify your electric company before you install.
• Virginia (from 2027): notify the utility on the State Corporation Commission form before you install.
• Maine: notify the utility within 30 days if your system is above 420 W.
• Colorado and New Hampshire: the utility may ask you to report the device and its size.
• Utah, Vermont and Connecticut: the utility may not require approval, fees or extra equipment.

Even where no notice is required, ask your utility how your meter counts power flowing out. Connecticut's law requires a consumer warning that, without a meter that allows net metering, power you send out can be charged to you. Maryland's Public Service Commission warns that, depending on the meter, power fed back may be counted as zero or added to your use.

Renters, condos and HOAs

If you do not own the building, the owner has a say. Some laws spell it out:

• Vermont: a tenant gives the landlord at least 10 days' notice. The landlord may set reasonable conditions, such as the tenant paying for electrical work; with no answer in 10 days, the tenant may go ahead.
• Maine: on a building you do not own, you must not damage the structure, must follow building, fire and zoning codes, and must restore it when you remove the kit.
• Colorado: from January 1, 2027, an HOA or covenant may not unreasonably prohibit a device; owners may set reasonable restrictions such as prior notice and location.
• New Jersey (from March 2027): landlords and HOAs may not broadly prohibit the devices.
• Virginia (from 2027): landlords with more than four units may not ban them.

Elsewhere your lease, condo rules or HOA rules decide. Ask in writing before you buy.

What our quiz does in each case

Our quiz finds your state from your ZIP code and shows it so you can correct it. Then:

• Law in force: we size a kit and use the state's lower "plug in yourself" limit as the default cap, for example 420 W in Maine. Where the law allows more with an electrician, we show that as a separate "with an electrician" option.
• Law signed, not yet in force: we tell you the start date and offer off-grid, portable or backup options meanwhile. From the start date, the quiz sizes plug-in kits for that state on its own.
• Pending, unclear or no law: we explain why we show no kit and offer the other options.
• No certified kit fits your limit: we say so rather than recommend a kit that fails our rule.

How we size systems is on our methodology page.

What to check before you buy

1. Find your state above and check the start date.
2. Check who your utility is. In Utah, a co-op or city utility may have its own rules.
3. Compare the kit's AC output with your state's limits, including the lower "plug in yourself" number.
4. Ask for the lab, the standard and a certificate number you can look up.
5. Ask your utility about notice and how your meter counts power flowing out.
6. Renters and HOA members: get permission in writing.
7. Ask your home insurer. New Hampshire's law asks its Department of Energy to warn that unlisted systems may affect insurance.

What can go wrong

• Too big for the state limit. An 800 W kit in Maine needs an electrician and a dedicated circuit; plugging it in yourself breaks the law.
• Old wiring. If outlets feel warm, breakers trip often or the wiring is old, ask an electrician first.
• Power strips and extension cords. Colorado allows only one device per outlet. Plug straight into a wall outlet and follow the maker's instructions.
• Meter surprises. On some meters, power you send out may show up as usage.

Questions people ask

Do I need an electrician? Not in the in-force states if the kit stays within the plug-in limit and your wiring is sound. In Maine above 420 W, yes. If you are unsure about your wiring, always ask one.

Will I be paid for power I send to the grid? Generally no. Utah, Maine and Vermont exclude plug-in kits from net metering, and Vermont says exported power is not paid.

Your next step

Enter your ZIP code in our quiz: we check your state, apply its limit and size a kit from many years of local weather records. If plug-in is not allowed where you live yet, the quiz offers other options, such as an off-grid system for a cabin. The state rules above were checked on October 20, 2026 and change often. This is not legal advice.

Our results and guides are estimates and do not replace advice from a qualified electrician.