How does solar permitting differ by state? On the East Coast it differs in the code overlay, the AHJ count, the utility interconnection application, and the incentive paperwork that people keep mixing into the building permit. Massachusetts is not Rhode Island. Connecticut is not New York. Pennsylvania is not a fifth copy of Massachusetts.
This is a comparison hub. It does not replace our longer 2026 state guides. Use those for checklists:
- Massachusetts solar permit requirements
- Rhode Island solar permitting
- Connecticut RRES
- NY-Sun
- Pennsylvania net metering and SRECs
Massachusetts
Many AHJs (hundreds of towns) under 780 CMR plus local habits. Stretch Energy Code in many places. Interconnection through National Grid, Eversource, Unitil, or an MLP. SMART is incentive, not PTO. Simplified vs Expedited vs Standard is the DG vocabulary. Structural PE shows up often because of snow and old houses. Details: the 2026 guide linked above.
Rhode Island
Fewer towns than Massachusetts, still not one packet. Rhode Island Energy is the IOU most crews meet. Simplified interconnection at 25 kW listed inverter on radial, then CEI, then Authorization to Interconnect. Do not energize early. Town permit is parallel. Details: the 2026 RI guide.
Connecticut
Two IOUs, Eversource and UI, both on PURA interconnection guidelines, both on PowerClerk, different portals. RRES is the incentive overlay and sometimes shares a ticket with interconnection at UI. Application fees for interconnection are published on Eversource’s Application to Connect page. Isolation-device location is a common drawing fail. Details: RRES guide plus the interconnection posts in this series.
New York
SIR for 5 MW or less, 50 kW split for small vs large DG, Con Edison PowerClerk vs upstate utilities vs Long Island. NYC DOB is not upstate permitting. NY-Sun is NYSERDA money. CESIR exists. No application fee at Con Edison ≤50 kW on their public page; $750 above. Details: NY-Sun guide plus the SIR vs Chapter 75 post.
Pennsylvania
Chapter 75 Levels 1 to 4. Level 1 is certified inverter-based 10 kW or less, which surprises crews who just left New York’s 50 kW band. PECO MyGeneration, PPL, FirstEnergy operating companies, Duquesne Light. PTO letter plus meters. AEPS / SREC / net metering are not the building permit. Details: PA net metering guide.
What is required in every state anyway
A solar permit (AHJ) and an interconnection application (EDC) and written permission to operate. Cut sheets, a diagram, a site plan. PE stamps when that AHJ or that track requires responsible charge. As-builts when the roof moved.
Solar permit requirements Massachusetts searchers should use the 2026 MA article. Solar permit New York and solar permit Connecticut searchers should use the NY-Sun and RRES articles plus this hub so we do not clone those URLs.
How we file across the map
One intake: survey, BOM, AHJ, utility. Then state-specific permit design, PE stamping with the correct license, and interconnection against that EDC’s portal. City pages exist for Boston, Worcester, Providence, Hartford, New Haven, NYC, Long Island, Albany, Philadelphia, Pittsburgh.
If you work two states, keep two checklists. That is how solar permitting differs by state, in practice: not a vibe, a file name.
Cross-border crews
If your office is in Massachusetts and you sell Rhode Island next month, the PE license and the utility portal both change. How solar permitting differs by state is mostly that sentence. Train PMs on two checklists. Do not “use the MA set and change the title block.”
Connecticut’s two PowerClerk instances are a smaller version of the same lesson inside one state.
What we will not duplicate here
Full AHJ lists, SMART tranche tables, NY-Sun block pricing, and SREC market chatter go stale. The five live guides plus the interconnection posts in this series carry that detail. This hub exists so a search for state differences lands on a map, then a link.
Athol Energy’s job is to keep the plan set and the interconnection application on the correct side of each border. Send the address. The state does the rest of the routing.
Incentive vs permit vs PTO, one more time
SMART, RRES, NY-Sun, and SRECs are not solar permit requirements. They are not permission to operate. How solar permitting differs by state includes how often people mix those three. Keep three folders. Your future self will be less angry.
If you only remember one row: Pennsylvania Level 1 is 10 kW, New York small-DG is 50 kW, Rhode Island Simplified is 25 kW listed inverter, Massachusetts Simplified is the small listed inverter path on the live M.D.P.U. process page, Connecticut small inverter guidelines sit near 25 kW on Eversource’s fee table. Those cutoffs are why solar permitting and interconnection differ by state in the first week of a job.