Every settled peak
ERCOT 4CP dates
Every settled coincident peak since 2022, and the 2026 season as it develops. ERCOT never announces these in advance. A peak is only official months later, when settlement data is final. Until then, there's the forecast.
Summer 2026, live
provisional until ERCOT settles each month| Month | Peak day | Hour (CT) | Load |
|---|---|---|---|
| June | Thu, Jun 19 | 4:00 PM CT | 77.4 GW |
| July | Wed, Jul 30 | 5:00 PM CT | 81.7 GW |
| August | Mon, Aug 18 | 5:00 PM CT | 83.7 GW |
| September | Thu, Sep 4 | 5:00 PM CT | 79.9 GW |
| Month | Peak day | Hour (CT) | Load |
|---|---|---|---|
| June | Sun, Jun 30 | 5:00 PM CT | 79.7 GW |
| July | Mon, Jul 1 | 5:00 PM CT | 81.0 GW |
| August | Tue, Aug 20 | 5:00 PM CT | 85.2 GW |
| September | Thu, Sep 19 | 4:00 PM CT | 77.8 GW |
| Month | Peak day | Hour (CT) | Load |
|---|---|---|---|
| June | Tue, Jun 27 | 5:00 PM CT | 80.8 GW |
| July | Mon, Jul 31 | 4:00 PM CT | 82.9 GW |
| August | Thu, Aug 10 | 5:00 PM CT | 85.5 GW |
| September | Fri, Sep 8 | 4:00 PM CT | 84.3 GW |
| Month | Peak day | Hour (CT) | Load |
|---|---|---|---|
| June | Thu, Jun 23 | 4:00 PM CT | 76.7 GW |
| July | Wed, Jul 20 | 4:00 PM CT | 80.0 GW |
| August | Tue, Aug 2 | 4:00 PM CT | 78.5 GW |
| September | Tue, Sep 20 | 4:00 PM CT | 71.0 GW |
When are the ERCOT 4CP dates announced?
They aren't announced in advance, and not immediately after either. A month's coincident peak is only official once ERCOT settlement data is final, which lags by months. During the summer you only ever know the month-to-date leader, which is why forecasting the peak days matters.
What months count for 4CP?
June, July, August, and September. ERCOT takes the single highest 15-minute system demand interval in each of those four months. Your average load across those four intervals sets your transmission cost share for the following year.
What time of day do 4CP peaks happen?
Almost always on hot weekday afternoons. Every settled peak from 2022 through 2025 landed between 3 PM and 6 PM Central. Solar has been pushing the peak later in the afternoon as the net-load peak shifts.
How do I know if today will be a 4CP day?
You can't know for certain until the month ends, but you can forecast it. WattMarkets publishes a daily probability and a tight window, free, and grades every call against official settlements.
Source: ERCOT official settled hourly load. Peak hours shown at hourly resolution; ERCOT's official 15-minute intervals are published after final settlement. Free to republish with a link: "Peak data by WattMarkets".
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