NOTICE DATE: October 7, 2026

NOTICE TYPE: M-A092826-03 Outage - Retail/Wholesale

SHORT DESCRIPTION: Planned system maintenance with impacted services

INTENDED AUDIENCE: ERCOT Market Participants

DAYS AFFECTED: October 8, 2026, 07:00 - 19:30 

LONG DESCRIPTION: ERCOT will be performing planned system maintenance of several databases and applications on October 8, 2026.

During the October 8, 2026, 07:00 - 08:00 outage window, CRR Market User Interface (MUI) will be unavailable to CRR Account Holders and Counter-Parties.

During the October 8, 2026, 11:00 - 15:00 outage window, Market Participants may experience intermittent issues with the following services:

Find ESIID

During the October 8, 2026, 13:30 - 15:00 outage window, Market Participants may experience intermittent issues with the following services:

ERCOT.com
RIOO-RS

During the October 8, 2026, 17:30 - 19:30 outage window, all services available through the Market Information System (MIS) will be unavailable, including the following:

Report publishing to the ERCOT MIS
Downloading of extracts and reports from the MIS and EWS
Net Dependable Capability and Reactive Capability (NDCRC)
Congestion Revenue Right (CRR) Market User Interface
Find ESIID and Find Transaction
Market Participant Identity Manager (MPIM)
Market Data Transparency (MDT) Web Services
Extract Subscriber
Service Requests

During this outage window, please use the following URLs to directly access the Market Manager, CRR Market User Interface, and Outage Scheduler: 

https://mis.ercot.com/mmsui/mmsui/displayTradesLanding.action
https://mis.ercot.com/mui-ercot-ihedge/
https://mis.ercot.com/osrui/osrui/Summary.action

During the October 8, 2026, 16:30 - 18:00 outage window, Market Participants may experience intermittent issues with the following services:

Market Participant Identity Manager (MPIM)
The following ERCOT internet services:
Renewable Energy Credit -  https://sa.ercot.com/rec/home
ERCOT Interconnection Services (GINR) -  https://sa.ercot.com/ginr/
Net Dependable Capability and Reactive Capability (NDCRC)

Note that the outage start times may be delayed depending on the current system conditions.

ADDITIONAL INFORMATION: Reports will be rerun and reposted as applicable. ERCOT.com dashboard displays will not be populated with data during the October 8, 2026, 17:30 - 19:30 timeframe.

CONTACT: If you have any questions, please contact your ERCOT Account Manager. You may also call the general ERCOT Client Services phone number at (512) 248-3900 or contact ERCOT Client Services via email at ClientServices@ercot.com.

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