If you are a Pepco customer in Maryland, the steady climb in your electricity bill hasn’t let up. Pepco has filed two rounds of Maryland tariff changes this cycle. Case No. 8890 raises the Transmission Service Charge across every rate class, effective September 1, 2026. Separately, a companion SOS filing — Cases 9056, 9064, 9478, and 9778, plus Rider “PC44” — locks in new supply generation rates running through May 31, 2027, and updates the Green Rider. Stacked against where rates stood in late 2024, every fixed-rate class we track is paying meaningfully more for the supply portion of its bill, and the increases keep coming: rates have climbed in nearly every rate-setting period since late 2024.
Important: These figures cover the supply portion of your bill — the SOS generation charge (including the administrative charge) plus the Transmission Service Charge under Case No. 8890. Distribution charges, taxes, and other riders are billed separately and continue to be regulated by the Maryland Public Service Commission.
So what keeps pushing these rates higher? The new transmission charge is only part of the story. Most of the pressure comes from the same regional forces driving up Pepco’s District of Columbia rates: record PJM capacity prices, a wave of power-plant retirements across the region, and rising demand from data centers inside the same PJM footprint Pepco draws from. Here is what the Maryland numbers show.
The Numbers: Supply Rates Climbed Again for 2026
Pepco’s Maryland SOS schedule sets all-in electricity supply charges — generation (including the administrative charge) plus the Transmission Service Charge — across several rate classes, using each schedule’s own rate-setting windows. Table A tracks the Residential and Type I Non-Residential classes (R, GS, T) from Winter 2024-25 through the newly filed Winter 2026-27 window.
Table A. All-in Pepco Maryland SOS supply rate ($/kWh) by billing period, Winter 2024-25 through Winter 2026-27 — Residential & Type I Non-Residential (R, GS, T). Includes the SOS generation charge (with administrative charge) plus the Transmission Service Charge under MD Case No. 8890.
| Period | R | GS | T |
|---|---|---|---|
| Winter 24/25 | $0.12457 | $0.11678 | $0.11315 |
| Spring ‘25 | $0.12655 | $0.11882 | $0.11519 |
| Summer ‘25 | $0.12348 | $0.11529 | $0.11166 |
| Winter 25/26 | not on file | not on file | not on file |
| Spring ‘26 | $0.13127 | $0.12291 | $0.12274 |
| Summer ‘26 | $0.13175 | $0.12458 | $0.12441 |
| Winter 26/27 | $0.14677 | $0.13706 | $0.13689 |
Rate classes: R (Residential), GS (Type I Non-Residential, general service), T (Type I Non-Residential). Winter runs October–January, Spring runs February–May, and Summer runs June–September, except Winter 2026-27, which Pepco filed as one longer window running October 2026 through May 2027. No SOS filing covering Winter 2025-26 was among the documents we reviewed, so that row is marked “not on file” rather than estimated.
Year-over-year changes
Table B converts that history into percentage change, season to season, ending with how far each class has moved since Winter 2024-25 — the start of this window — to the newly filed Winter 2026-27 rate.
Table B. Percentage change in Pepco Maryland SOS supply rates, season to season, Winter 2024-25 through Winter 2026-27
| Rate Class | Winter ‘24/25 → Spring ‘25 |
Spring ‘25 → Summer ‘25 |
Summer ‘25 → Spring ‘26 |
Spring ‘26 → Summer ‘26 |
Summer ‘26 → Winter ‘26/27 |
Winter ‘24/25 → Winter ‘26/27 |
|---|---|---|---|---|---|---|
| R — Residential | +1.6% | –2.4% | +6.3% | +0.4% | +11.4% | +17.8% |
| GS — Type I Non-Residential | +1.7% | –3.0% | +6.6% | +1.4% | +10.0% | +17.4% |
| T — Type I Non-Residential | +1.8% | –3.1% | +9.9% | +1.4% | +10.0% | +21.0% |
What the table shows
The last column tells the story: every class we track is running 17.4–21.0% above where it stood in Winter 2024-25. Schedule T has moved the most. Through most of the sequence it tracks GS almost exactly — both jump about +10% into Winter 2026-27 — but T’s two-year total ends up nearly four points higher. That gap traces to the new Transmission Service Charge taking effect under MD Case No. 8890 on September 1, 2026: transmission is a small slice of the total bill, but Schedule T’s transmission charge alone is rising nearly 50%, more than five times the percentage increase Residential customers will see on that same line item.
The biggest single step for every class is Summer ‘25 to Spring ‘26 (+6.3% to +9.9%) — larger than the move into summer itself, and the period that includes the January 2026 rate reset. From there, R, GS, and T move together in smaller steps through the rest of the window.
Type II customers (MGT LV II, MGT 3A II) aren’t in the tables above — that class reprices quarterly rather than on R/GS/T’s Winter/Spring/Summer cycle, so its billing windows don’t line up with these dates. The short version for Type II: it moves in sharper single-year swings, including a roughly +39% jump from the March–May 2026 window to the June–August 2026 window, on top of the same September 1 transmission increase. If Type II or Hourly Priced Service is your class, reach out and we can walk through your specific numbers.
What’s Driving the Increases?
The Maryland Public Service Commission doesn’t set generation prices — like the SOS rates across the District, those come from competitive wholesale auctions in the PJM market. This year’s Maryland rates reflect Pepco’s current SOS procurement, filed under Cases 9056, 9064, 9478, and 9778 and Rider “PC44,” plus the Case No. 8890 transmission increase — both layered on top of the same 2026-27 PJM Base Residual Auction capacity costs pushing up rates across the entire Pepco footprint. Several forces are converging.
Record PJM capacity prices. The 2026/27 PJM Base Residual Auction cleared at $329.17/MW-day across the entire PJM footprint, the FERC-approved cap price and the highest in PJM history, up about 22% from $269.92/MW-day the prior year. PJM Interconnection, the regional grid operator, hit the price cap as it struggled to meet reliability targets amid tightening supply.
Data-center demand, and why Virginia’s growth lands on a Maryland bill. This one causes confusion, so it is worth being precise. Northern Virginia’s data centers are not outside the regional grid pressing in on it. They are inside it. Dominion Energy Virginia has been a PJM member since 2005, and its service territory is a full PJM transmission zone. Loudoun County’s “Data Center Alley” sits in that zone, in the same capacity market Pepco buys from.
PJM builds a single reliability requirement for the entire footprint from one regional load forecast, then procures capacity against a regional supply stack. Demand growth concentrated in one zone therefore raises the clearing price for every zone, including Pepco’s. And the concentration is extreme: weather-normalized baseload in the Dominion zone has grown roughly 6.5% per year since 2021, about four times the PJM-wide average of 1.63%. PJM attributed a year-over-year increase of more than 5,400 MW in forecast peak load for the 2026/27 delivery year largely to data-center expansion, electrification, and economic growth.
The scale of the effect is not speculative. Monitoring Analytics, PJM’s independent market monitor, estimated that data centers were responsible for 63% of the capacity price increase in the 2025/26 auction, amounting to roughly $9.3 billion in additional costs recovered from customers across PJM in a single delivery year.
Power-plant retirements. Older generation across the PJM footprint continues to retire faster than new capacity comes online. That squeezes the supply-demand balance and lifts wholesale prices.
Renewable mandates. Maryland’s renewable-energy requirements contribute to supply costs, though wholesale market conditions remain the dominant driver.
On top of all this, growing liquefied natural gas exports may place upward pressure on domestic natural gas prices over time, although weather and production levels remain major drivers. Natural gas is still the largest single fuel source for electricity generation.
A note of balance. Rates are not guaranteed to keep climbing at this pace, and there is early evidence of a plateau. PJM’s most recent capacity auction, for the 2027/28 delivery year, cleared at $333.44/MW-day. That is a third consecutive record, but it is only about 1.3% above the prior year, compared with the 22% increase the year before. New generation projects, transmission upgrades, or lower natural gas prices could moderate costs further. Electricity markets remain inherently cyclical.
Hourly Priced Services
Rate Classes Included: MGT LV III, MGT 3A III, GT LV, GT 3A, GT 3B, and TM-RT
For MGT LV III, MGT 3A III, GT LV, GT 3A, GT 3B, and TM-RT, riding Hourly-Priced Service (HPS) means your supply cost floats with PJM’s locational marginal price every hour — then Pepco layers on admin and ancillary charges, plus a separate monthly capacity charge. There’s no cap, and heat waves, grid constraints, or market events can push costs multiple times higher within days.
Looking at the fixed-rate classes over the full Winter 2024-25–Winter 2026-27 window (Tables A and B) makes that risk easier to size. Even Residential, GS, and T — the calmest classes we track, with gentle seasonal moves of a few percent period to period — are running 17.4–21.0% above where they stood in Winter 2024-25. Type II (MGT LV II) is more dramatic within a single year, with a roughly +39% Mar–May-to-Jun–Aug swing already built into the 2026 schedule. HPS customers absorb that same underlying generation cost growth in real time, with no seasonal averaging window to smooth it out.
On top of that, Case No. 8890 — the same filing raising transmission charges for R, GS, T, and MGT LV II — also raises the fixed transmission component for every HPS class, effective September 1, 2026: MGT LV III and MGT 3A III move to $0.00832 and $0.00848 per kWh; GT LV, GT 3A, and GT 3B to $0.00773, $0.00746, and $0.00603 per kWh; and TM-RT to $0.00749 per kWh — each with updated per-kW on-peak and maximum demand charges alongside. That’s a smaller share of an HPS bill than the hourly energy charge, but it’s one more cost moving in the same direction, on top of the market exposure that makes HPS harder to budget for in the first place.
How Honeydew Helps You Take Control
As supply rates keep climbing, good guidance pays for itself. Honeydew Energy Advisors manages over 1,000 utility accounts and helps building owners navigate DC and Maryland benchmarking and BEPS compliance while reducing energy costs through procurement, solar, and efficiency strategies. Whether you operate a multifamily building or a commercial portfolio, we can benchmark your accounts against our portfolio, compare supplier rates and help you lock in more competitive fixed electricity contracts, support solar adoption through rooftop or community solar, administer your Energy Star Portfolio Manager reporting, and recommend efficiency upgrades that lower consumption over the long term.
We also serve as your ongoing energy advocate. We track market trends and Pepco filings so you stay ahead of the next change, we negotiate on your behalf, and we explain what shifting rates mean for your budget.
Looking Ahead
As AI, electrification, and LNG exports keep scaling, their effect on electricity costs will keep growing. Pepco’s rising rates reflect that larger shift, and they are a good reason for consumers to get more deliberate about how they buy and use power. The future is electric, but it does not have to be unpredictable. With Honeydew Advisors on your side, you can plan around rate increases instead of reacting to them.
Call us at 202-670-9625 to talk to an advisor.