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- UL 3700 was published in December 2025, so certifications only began arriving in 2026.
- Reported early certifications: the Hoymiles HiFlow microinverter used in Bright Saver kits, and APsystems’ EZ1-LV microinverter (July 2026).
- Craftstrom, EcoFlow STREAM and APsystems’ EZ1-M kits were reported as in progress.
- States like New Jersey and Maine name UL 3700 or equivalent; others accept any NRTL listing.
If your state requires UL 3700, your choice in late 2026 is narrow. That is not a sign the other kits are unsafe, only that certification takes time and money. Here is where things stood. What UL 3700 tests.
In this article
Status by product
| Product | Type | Reported UL 3700 status (Sept 2026) |
|---|---|---|
| Bright Saver Balcony Solar Kit | Complete kit (180/360 W) | Uses the Hoymiles HiFlow microinverter, reported as the first UL 3700 certified microinverter |
| APsystems EZ1-LV | Microinverter | Reported certified, July 15, 2026 |
| APsystems EZ1-M kit | Kit | System-level certification pending |
| Craftstrom Smart Kit | Kit | Application filed |
| EcoFlow STREAM microinverter | Microinverter | In progress |
| EcoFlow STREAM Ultra | Battery system | Dual certification pending (UL 3700 and UL 1973) |
Compiled from tracker reports and manufacturer statements. Verify with the certifying laboratory’s database before you buy.
Component vs system certification
Several listings above cover the microinverter, not the whole kit. Some states and some reviewers draw a distinction; Bright Saver, for example, paused sales in New York, Maine and Vermont pending whole-system certification requirements. If your state names UL 3700, ask the seller directly whether the complete product you are buying is certified.
How to verify
- Find the certification mark and file number on the product label or manual.
- Search the file number in UL Product iQ (or the database of the lab that certified it, such as Intertek or CSA).
- Confirm the listing covers the model number you are buying.
- Save a PDF of the listing for your landlord, utility notification or insurer.
What if my state doesn’t require UL 3700?
Utah, Virginia, Maryland, Connecticut, Vermont and Colorado generally require a listing by a nationally recognized testing laboratory. A microinverter listed to UL 1741 with anti-islanding may satisfy that. UL 3700 is still the better choice when available, because it addresses plug-specific hazards. See your state’s wording.
See Bright Saver See APsystems
What to buy while the list is short
- If you are in a state that names UL 3700: a kit built around a certified microinverter, and confirmation from the seller that the product qualifies.
- If your state accepts any NRTL listing: a kit with a UL 1741-listed microinverter from a major brand, ideally one with UL 3700 certification in progress.
- If your law is not in effect yet: wait; more certified products will arrive.
Questions to ask a seller
- Is the complete product certified to UL 3700, or only the microinverter?
- Which laboratory issued the certification, and what is the file number?
- Does the certification cover the exact model and configuration I am buying?
- Is the product approved for sale in my state, or are sales paused pending requirements?
- What is the maximum AC output, and can it be limited for my state’s cap?
A reputable seller answers these quickly and in writing.
Frequently asked questions
Why not just buy a UL 1741 kit?
In states that accept any nationally recognized listing, a UL 1741 microinverter may be fine. UL 3700 adds plug-specific protections and is named in New Jersey and Maine. If you might move to such a state, UL 3700 is the safer bet.
How often is this list updated?
We review certification news monthly and whenever a manufacturer announces a listing.
Does a certified microinverter make my DIY kit certified?
No. System certification covers a specific combination. A certified microinverter is still the most important component to get right.