MISO Day-Ahead Ancillary Prices

Cleared day-ahead ancillary-service capacity prices in MISO, one row per hour, ASM reserve zone and product.

Ancillary Services data MISO market

Query with the agent

Native record

product x region x delivery hour

hourly (day-ahead) publication cadence

Evidence

Cleared day-ahead market

A market outcome, not a physical observation

Time basis

Interval-start records

UTC · event_time

Overview

74,976 rows, 2026-08-12 to the next delivery day. Products: reg_up, spin, supplemental, short_term_reserve, ramp_up, ramp_down. Prices clear per ASM reserve zone, '1' through '8'; a MISO-wide figure is not published and must not be invented by averaging the zones. price_usd_mw is a price for CAPACITY held in reserve — dollars per megawatt of commitment — not dollars per megawatt-hour of energy delivered. The two are different units and are not comparable to an LMP.

Query contract

Select one product and one region before aggregating. Each row is already the canonical cleared price for that combination.

Analysis rules

Never sum prices across products. Reserve products are separately procured markets and their prices do not add to a meaningful total.
Never sum or average across ASM reserve zones without saying so; prices clear per asm reserve zone, '1' through '8'; a miso-wide figure is not published and must not be invented by averaging the zones.

Interpretation

price_usd_mw is $/MW of capacity held, not $/MWh of energy. Do not compare it directly to an LMP, and do not multiply it by megawatt-hours.
A cleared price is what the day-ahead market settled at. It is not the quantity procured, not a scarcity measurement, and not evidence that reserves were short.

Access

Query from your own tools

Use the guarded HTTP endpoint directly, or connect an MCP client and load the dataset contract with describe_data before calling query_data.

MISO MCP API reference

HTTP endpoint

POST /api/v1/datasets/miso_ancillary_da/query

Need the full history of this dataset in Snowflake, Databricks or your own storage? Data services delivers it on a schedule.

Schema4

Column

Type

event_timeDateTime64(6, 'UTC')

regionLowCardinality(String)

productLowCardinality(String)

price_usd_mwNullable(Float64)

Sample data

event_time	region	product	price_usd_mw
2026-10-17 04:00:00.000000	4	ramp_down	0
2026-10-17 04:00:00.000000	2	spin	2.5
2026-10-17 04:00:00.000000	7	spin	2.5
2026-10-17 04:00:00.000000	1	spin	2.5
2026-10-17 04:00:00.000000	5	ramp_down	0
2026-10-17 04:00:00.000000	8	short_term_reserve	0
2026-10-17 04:00:00.000000	1	ramp_down	0
2026-10-17 04:00:00.000000	6	ramp_down	0
2026-10-17 04:00:00.000000	3	spin	2.5
2026-10-17 04:00:00.000000	6	short_term_reserve	0
2026-10-17 04:00:00.000000	1	reg_up	18.52
2026-10-17 04:00:00.000000	7	ramp_down	0
2026-10-17 04:00:00.000000	5	short_term_reserve	0.2
2026-10-17 04:00:00.000000	4	short_term_reserve	0.2
2026-10-17 04:00:00.000000	8	ramp_down	0
2026-10-17 04:00:00.000000	3	short_term_reserve	0.2
2026-10-17 04:00:00.000000	2	reg_up	18.52
2026-10-17 04:00:00.000000	7	short_term_reserve	0
2026-10-17 04:00:00.000000	6	reg_up	18.52
2026-10-17 04:00:00.000000	6	ramp_up	0
2026-10-17 04:00:00.000000	3	reg_up	18.52
2026-10-17 04:00:00.000000	5	ramp_up	0
2026-10-17 04:00:00.000000	8	spin	2.5
2026-10-17 04:00:00.000000	4	ramp_up	0
2026-10-17 04:00:00.000000	5	reg_up	18.52

Coverage

No time-indexed data — coverage isn’t applicable to this dataset.

Related ancillary services data

Related ancillary services data
Dataset	Description
Live Ancillary-Service PricesMISO · 1-minute snapshots	Real-time and day-ahead ancillary-service clearing prices for each of MISO's eight reserve zones. Keep zone and product explicit; averaging reserve-zone prices would create a market-wide price MISO does not publish.
Look-ahead regional reportMISO · day publication	MISO's Look-ahead regional report. Each row preserves a publisher record, workbook row, or report document with its source member and row index. Source timestamps, units, geographic scope, and revision qualifiers are retained in record_json; event_time is collection time; completed_at is when the entire document became available.
Multiday operating margin workbook, all regions/sheetsMISO · day publication	MISO's Multiday operating margin workbook, all regions/sheets. Each row preserves a publisher record, workbook row, or report document with its source member and row index. Source timestamps, units, geographic scope, and revision qualifiers are retained in record_json; event_time is collection time; completed_at is when the entire document became available.
Ancillary Service Market Clearing PricesSPP · 5-minute (RTBM) and hourly (Day-Ahead)	Cleared ancillary-service prices by SPP reserve zone for both the real-time balancing market and the day-ahead market. SPP's product set does not map onto other ISOs': regulation clears as a separate service (capacity) price and mileage price in each direction (reg_up_service, reg_up_mile, reg_dn_service, reg_dn_mile), alongside ramp up and down, spinning, supplemental, and uncertainty products. IMPORTANT: reserve_zone mixes two grains. It carries the numeric ancillary reserve zones (1 through 5 under the SPP balancing authority, 21 under the separate SWPW balancing authority) AND the two balancing-authority roll-ups, 'SPP' and 'SWPW', whose prices equal those of their member zones. Aggregating across every value of reserve_zone double-counts the market.