IESO Ontario Zonal Price

The Ontario zonal price, the load-weighted price Ontario's non-dispatchable load pays, in each market run, with loss and congestion components.

Prices data IESO market

Query with the agent

Native record

market run x interval

five-minute real-time; hourly day-ahead and pre-dispatch publication cadence

Evidence

Mixed evidence

Multiple evidence types kept distinct in the contract

Time basis

Point-in-time records

UTC · event_time

Overview

Ontario's reference price.

Query contract

Preserve one canonical row per (event_time, market_run, zone_name) before aggregating.

Analysis rules

Filter one market_run: 'rt_5min' (real-time, five-minute), 'da_hourly' (day-ahead market) or 'predispatch_hourly' (pre-dispatch projection). Never mix runs, and never take max(event_time) without one: day-ahead rows reach into tomorrow.
Rows repeat across polls: dedupe with argMax(value, ingested_at) per key.

Interpretation

event_time marks the END of the interval or hour. IESO delivers on EST all year, but this mirror's event_time was built on Toronto wall time, so between the second Sunday of March and the first Sunday of November it is one hour early. The delivery end is event_time + toIntervalSecond(timeZoneOffset(toTimeZone(event_time, 'America/Toronto')) + 18000); rows in the spring-forward hour cannot be placed. Toronto civil time is for display only.
Prices are Canadian dollars per MWh. Never add, rank or average them with US-dollar prices without a dated exchange rate, and say which rate was used.

Access

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

Schema8

Column

Type

event_timeDateTime64(6, 'UTC')

market_runLowCardinality(String)

zone_nameLowCardinality(String)

lmpNullable(Float64)

congestionNullable(Float64)

lossNullable(Float64)

publish_timeNullable(DateTime64(6, 'UTC'))

ingested_atDateTime64(6, 'UTC')

Sample data

event_time	market_run	zone_name	lmp	congestion	loss	publish_time	ingested_at
2026-10-12 04:00:00.000000	da_hourly	Ontario	42.74	∅	0.26	∅	2026-10-10 17:35:30.740095
2026-10-12 03:00:00.000000	da_hourly	Ontario	51.75	-0.06	0.16	∅	2026-10-10 17:35:30.740095
2026-10-12 02:00:00.000000	da_hourly	Ontario	54.05	-0.07	0.04	∅	2026-10-10 17:35:30.740095
2026-10-12 01:00:00.000000	da_hourly	Ontario	58.19	-0.01	-0.01	∅	2026-10-10 17:35:30.740095
2026-10-12 00:00:00.000000	da_hourly	Ontario	60.82	∅	0.03	∅	2026-10-10 17:35:30.740095
2026-10-11 23:00:00.000000	da_hourly	Ontario	75.22	∅	0.1	∅	2026-10-10 17:35:30.740095
2026-10-11 22:00:00.000000	da_hourly	Ontario	80.54	∅	0.15	∅	2026-10-10 17:35:30.740095
2026-10-11 21:00:00.000000	da_hourly	Ontario	73.28	-0.08	0.02	∅	2026-10-10 17:35:30.740095
2026-10-11 20:00:00.000000	da_hourly	Ontario	61.22	-0.09	-0.03	∅	2026-10-10 17:35:30.740095
2026-10-11 19:00:00.000000	da_hourly	Ontario	60.61	-0.09	0.04	∅	2026-10-10 17:35:30.740095
2026-10-11 18:00:00.000000	da_hourly	Ontario	58.05	-0.08	0.03	∅	2026-10-10 17:35:30.740095
2026-10-11 17:00:00.000000	da_hourly	Ontario	56.64	-0.07	-0.01	∅	2026-10-10 17:35:30.740095
2026-10-11 16:00:00.000000	da_hourly	Ontario	53.66	-0.19	0.04	∅	2026-10-10 17:35:30.740095
2026-10-11 15:00:00.000000	da_hourly	Ontario	50.82	-1.53	0.06	∅	2026-10-10 17:35:30.740095
2026-10-11 14:00:00.000000	da_hourly	Ontario	43.98	-0.01	0.02	∅	2026-10-10 17:35:30.740095
2026-10-11 13:00:00.000000	da_hourly	Ontario	42.3	-0.01	0.16	∅	2026-10-10 17:35:30.740095
2026-10-11 12:00:00.000000	da_hourly	Ontario	41.42	-0.01	0.29	∅	2026-10-10 17:35:30.740095
2026-10-11 11:00:00.000000	da_hourly	Ontario	36.47	0.03	0.36	∅	2026-10-10 17:35:30.740095
2026-10-11 10:00:00.000000	da_hourly	Ontario	33.33	∅	0.29	∅	2026-10-10 17:35:30.740095
2026-10-11 09:00:00.000000	da_hourly	Ontario	37.83	∅	0.27	∅	2026-10-10 17:35:30.740095
2026-10-11 08:00:00.000000	da_hourly	Ontario	36.72	∅	0.22	∅	2026-10-10 17:35:30.740095
2026-10-11 07:00:00.000000	da_hourly	Ontario	36.4	∅	0.22	∅	2026-10-10 17:35:30.740095
2026-10-11 06:00:00.000000	da_hourly	Ontario	34.9	∅	0.19	∅	2026-10-10 17:35:30.740095
2026-10-11 05:00:00.000000	da_hourly	Ontario	32.96	∅	0.14	∅	2026-10-10 17:35:30.740095
2026-10-11 04:00:00.000000	predispatch_hourly	Ontario	31.8	-0.37	0.09	∅	2026-10-10 17:35:30.740095

Coverage

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

Related prices data

Related prices data
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