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How long does my NEM 2.0 grandfathering last?
Updated October 6, 2026 · using the CPUC 20-year legacy term · by Cali Energy
How long does NEM 2.0 grandfathering last in California? 20 years from your Permission to Operate (PTO) date. A system with a 2021 PTO keeps NEM 2.0 terms through about 2041 — roughly 15 years left as of 2026. After that you move to whatever tariff applies then.
✓ Uses the CPUC 20-year grandfathering term. See the rule ↓
Assumptions: the 20-year legacy period for NEM 1.0 and NEM 2.0 (CPUC D.14-03-041 and D.16-01-044), measured from the original PTO date and running through the true-up year that closes on or after the 20th anniversary (SCE and PG&E tariffs). A PTO in 2023–2026 counts only if the application was filed by April 14, 2023; later applicants are on the Net Billing Tariff. A planning estimate; your utility has the exact dates.
Have us confirm your tariff and PTO dateThe rates and figures this calculator usestap to verify
The rule is simple — 20 years from your PTO date — but the date matters, so here it is with its source and the math.
| Term | 20 years from your PTO date, through the true-up year that closes on or after the 20th anniversary |
| Applies to | systems with a qualifying complete interconnection application submitted by Apr 14, 2023 (PTO often came later) |
| After 20 years | you move to the then-current tariff |
| End year | PTO year + 20 |
| Years left | end year − the current year (2026) |
NEM 2.0 (and NEM 1.0) customers keep their net-metering terms for 20 years from the date their system received Permission to Operate (PTO), per CPUC Decisions D.14-03-041 (NEM 1.0) and D.16-01-044 (NEM 2.0). This counts 20 years from the PTO year you enter, so confirm your exact PTO date with your utility — it drives the end date. Note that the tariff follows the system, not the owner (it transfers with the home), and expanding your system beyond the greater of 1 kW or 10% can end legacy terms early; SCE applies the same limit to added storage, so check before adding a battery.
Example results you can reproduce
Each row counts 20 years from the PTO year, with time remaining measured from 2026 — enter the same year to reproduce it.
| PTO year | Grandfathered through | Years left (as of 2026) |
|---|---|---|
| 2018 | ~2038 | ~12 |
| 2021 | ~2041 | ~15 |
| 2022 | ~2042 | ~16 |
How this calculator works
It adds 20 years to the PTO year you enter to get your grandfathering end date, then subtracts the current year to show how long you have left. That’s the whole rule — the value is in reminding you that your favorable NEM 2.0 (or 1.0) terms aren’t forever, and in pinning down roughly when they end so you can plan a battery or an eventual tariff change.
How to read your result
The end year is when your legacy terms sunset; the years-left figure is your remaining runway of high-value net metering. It’s tied to the PTO year you enter, so verify your exact date with the utility for a precise month. Remember the clock keeps running for whoever owns the home — the grandfathering transfers with the property, it doesn’t reset for a new owner.
What moves the result the most
Only your PTO date — earlier systems have fewer years left. The one thing that can cut it short is a system expansion beyond the greater of 1 kW or 10%, which forfeits legacy status for the whole array. Otherwise the 20-year clock simply runs down to your end year.
Common questions
How long does NEM 2.0 last?
20 years from your system’s Permission to Operate date (CPUC D.16-01-044), through the end of that true-up year. After that you move to the then-current tariff.
What is PTO?
Permission to Operate — the date your utility formally authorized your system to connect and export. It’s the start of your 20-year grandfathering clock, printed on your interconnection paperwork.
When does my grandfathering end?
PTO year + 20. A 2020 PTO runs to about 2040. Enter your year above for the estimate and confirm the exact date with your utility.
What happens after 20 years?
Your system moves onto whatever net-metering or net-billing tariff is current then. It’s worth planning for — a battery can soften the change by letting you use more of your own power.
Does expanding my system reset or end it?
It doesn’t reset — and growing past the greater of 1 kW or 10% can end it early, moving the whole system to NEM 3.0. See our add-panels calculator.
Can I still get NEM 2.0 on a new system?
No — NEM 2.0 closed to new applications after April 14, 2023 (a complete interconnection application had to be submitted by then, though PTO could follow later). New residential solar goes on NEM 3.0 (the Net Billing Tariff).
Sources
- CPUC — Net Energy Metering and Net Billing (NEM 1.0, NEM 2.0 and Net Billing Tariff compared)
- CPUC — Net Energy Metering Rulemaking R.14-07-002 (utility transition dates to NEM 2.0)
- CPUC Decision D.14-03-041 — 20-year transition period, modifications and transfer rules
- CPUC Decision D.16-01-044 — NEM successor tariff (NEM 2.0)
- CPUC Decision D.22-12-056 — Net Billing Tariff, NEM 2.0 sunset, storage additions, nine-year legacy period
- SCE — Schedule NEM-ST, Net Energy Metering Successor Tariff (Special Conditions 8–10)
- PG&E — Electric Schedule NEM2, Net Energy Metering Service
- SCE — Solar Billing Plan (Energy Export Credit values)
- SCE — Base Services Charge (effective November 2025, applies to NEM and Solar Billing Plan customers)
- California Legislature — AB 942 (2025–2026) bill status
- SCE — Net Energy Metering FAQ (expansion limits also apply to added storage; “NEM 1.0/2.0 Expansion” application)
Estimates only, not a quote. Assumptions, rates, incentives and program rules can change — confirm current details with your utility, the program administrator or a licensed professional.
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