The Arbor Rate Forecast projects each utility's residential default supply rate — the 'price to compare' on your bill — across 20+ utilities in 8 states and DC. The underlying forecast is re-run weekly; this page reflects the latest published edition, dated above. The model projects several years out, though the table shows the 12-month view.
Most rate information tells you what you're paying today, or gives a generic estimate of what's "typical." We forecast forward instead, by rebuilding each rate from the wholesale costs utilities actually procure. A wholesale-energy layer draws on PJM/ISO-NE power markets and natural gas curves; a capacity layer draws on PJM's annual capacity auction; and a procurement layer folds in each utility's own default-service auctions (PA's DSP, NJ's BGS, Ohio's SSO) as they clear. A model tuned to each utility then translates those inputs into that service area's posted rate — so the forecast reflects how that specific utility passes costs through, not a one-size-fits-all markup.
Every forecast carries a confidence tier — High, Medium, or Low — based on how closely the model has tracked real rates in past backtests; well-covered utilities usually land within a few percentage points of the actual rate at the one-year mark, while areas with thinner auction history or recent regulatory changes get wider ranges and lower confidence, shown plainly rather than buried.
How accurate it's been. We grade every forecast in public. Each of the ~16,000 forecasts we've published since February 2024 is scored against the residential default supply rate that actually took effect, and the scorecard re-runs every Monday as new rates publish. Near-term forecasts, one to three months out, come in within about 2% of the rate that lands; across all horizons combined, our typical miss is about 8.4%, widening the further ahead we look. And our confidence ranges hold up — when we say we're 90% confident a rate will fall within a given range, it does about 90% of the time.
Read the forecast as a schedule of upcoming changes with uncertainty attached, not a single prediction of your future bill. Rates move in steps on each utility's reset date, and the further out the forecast looks, the wider that uncertainty gets.
