Oregon homeowners have a net metering explainer on this site. Washington homeowners deserve the same, because the rules are genuinely different — and the difference that matters most is a single date on the calendar: 30 April.
How does net metering work in Washington?
When your array makes more than the house is using, the surplus goes onto the grid and your meter credits you for it. When you draw more than you make — at night, in December — you use those credits before you buy power again. The mechanism is set out in state law under RCW 80.60.
You are not selling power in any meaningful sense. You are banking kilowatt-hours against your own later use, which is why sizing a system to your consumption matters more than sizing it to your roof.
What is the 30 April balance date?
This is the part people miss. Washington net metering accounts have an annual balance date of 30 April. Credits you have accumulated and not used are reconciled then rather than rolling forward indefinitely.
The timing is actually well matched to how solar behaves here. You build credit through the bright half of the year, draw it down through the dark half, and arrive at the end of April having used what you banked. What it does mean is that a system deliberately oversized to bank a big surplus is banking something with a shelf life — another reason to size against real annual usage rather than available roof.
How big a system can I net meter?
Systems up to 100 kilowatts qualify under the state programme. That is far beyond any home installation and comfortable for most small commercial roofs, so for residential purposes it is effectively not a constraint.
Does my utility have to offer it?
Washington law requires utilities to offer net metering, and the Utilities and Transportation Commission regulates the three investor-owned utilities in the state — Avista, Pacific Power and Puget Sound Energy. There is also a cumulative capacity limit written into the law, set as a share of each utility’s peak demand.
In our service area, though, most homes are served by consumer-owned public utility districts rather than an investor-owned company. Clark Public Utilities and Cowlitz PUD set their own programme terms within the law, and the details — how excess is credited, what the interconnection application looks like, what happens at the balance date — are theirs. We confirm the current terms with your specific utility before designing a system rather than assuming a statewide default.
How is this different from Oregon?
The mechanics rhyme, but the terms and the reconciliation timing differ, and the incentive landscape around them differs a great deal more. Oregon’s Energy Trust incentives, for example, are funded by and limited to Portland General Electric and Pacific Power customers. Our Oregon net metering explainer covers that side.
If you own property on both sides of the river — which is common enough around Vancouver and Portland — treat them as two separate questions rather than one.
What does this mean for sizing?
Three practical rules follow from the way Washington net metering works:
- Size against twelve months of usage, not against the largest array your roof could hold
- Account for loads you are about to add — a heat pump or an EV changes the target materially
- Use what you make when you can. A kilowatt-hour consumed as it is produced is worth more than one exported and reclaimed later, so shifting the dishwasher, the water heater or the car charging into daylight quietly improves the return
Frequently Asked Questions
How does net metering work in Washington state?
Surplus production goes to the grid and credits your account; you draw those credits down when you use more than you produce. It is governed by RCW 80.60, and the credits are kilowatt-hours banked against your own later use rather than a cash payment.
When do Washington net metering credits expire?
Net metering accounts have an annual balance date of 30 April, when accumulated credits are reconciled rather than carried forward indefinitely. That timing suits the Pacific Northwest solar year, but it is a reason not to deliberately oversize a system.
What size solar system can be net metered in Washington?
Up to 100 kilowatts qualifies under the state programme — far above any residential installation, so for homes it is not a practical limit.
Does Clark PUD or Cowlitz PUD offer net metering?
Consumer-owned utilities operate their own programmes within state law, so the specific terms are set by your utility rather than by the UTC, which regulates the three investor-owned utilities. We confirm current terms with your utility before designing a system.
Is Washington net metering the same as Oregon’s?
The mechanics are similar but the terms and reconciliation timing differ, and the surrounding incentives differ more — Oregon’s Energy Trust programmes are limited to PGE and Pacific Power customers. Treat properties on either side of the river as separate questions.
Not sure how your utility handles it?
Call 360-313-7190 and we will check the current terms for your address before anyone talks about system size. Sunbridge Solar serves Camas, Washougal, Vancouver, Portland and the Columbia River Gorge.
