Market Snapshot: Oil pipeline throughputs remained high in 2025

Release date: 2026-06-24

In 2025, throughput on Canada’s three largest crude oil pipelines (Enbridge Canadian Mainline, Keystone pipeline, and Trans Mountain System) remained high. These pipelines transport oil from the Western Canada Sedimentary Basin (WCSB) to Canadian, United States (U.S.), and other international destinations.

Enbridge Mainline maintains steady throughput in 2025

At the Enbridge Mainline’s ex-Gretna^Footnote 1 key point in Manitoba at the U.S. border, throughput averaged 3.08 million barrels per day (MMb/d) in 2025, less than a 1% increase from 3.06 MMb/d in 2024. Throughput has remained relatively constant since 2023. A monthly high throughput for 2025 was reached in December at 3.24 MMb/d.

In 2025, available capacity averaged 3.23 MMb/d, ranging from 3.16 MMb/d in September to 3.28 MMb/d in December.^Footnote 2 Utilization averaged 95.2%, the highest annual average since 2019. The Enbridge Mainline remained apportioned in most months in 2025 on certain heavy crude oil and light crude oil lines at the key point of Kerrobert, Saskatchewan, as well as on heavy crude oil lines on the U.S. portion of the system in Superior, Wisconsin. Apportionment has generally been below 10% each month following the startup of the Trans Mountain Expansion Project in May 2024, which eased export pipeline constraints.^Footnote 3

Figure 1: Monthly throughput and available capacity on Enbridge Mainline (ex-Gretna)

Keystone throughputs and available capacity decreased after record high in 2024

In 2025, the Keystone pipeline transported an average of 585 thousand barrels per day (Mb/d), compared to an annual record high of 624 Mb/d set in 2024. Available capacity averaged 607 Mb/d in 2025, also a decrease from the 2024 record high of 626 Mb/d.

An oil release incident in North Dakota in April 2025^Footnote 4 temporarily shut down the pipeline and resulted in the monthly average throughput dropping from nearly 600 Mb/d in March to 446 Mb/d in April. About a week after the incident, South Bow received approval from the Pipeline and Hazardous Materials Safety Administration (PHMSA) to restart with reduced operating pressures. These pressure restrictions kept Keystone’s monthly average throughputs below 600 Mb/d for most of the remainder of 2025, with volumes exceeding that level only in December.

Figure 2: Monthly throughput and available capacity on Keystone Pipeline

Trans Mountain throughputs continued to ramp up in 2025

Shipments on the Trans Mountain System continued to ramp up following the startup of the Trans Mountain Expansion Project in May 2024, averaging 85% utilization in 2025. It transported an average of 761 Mb/d in 2025, an increase of 37% from 555 Mb/d in 2024. A monthly throughput record high of 855 Mb/d (96% utilization) was reached in November 2025.

The Trans Mountain Expansion Project nearly tripled the capacity of the pipeline system. In 2025, available capacity averaged 892 Mb/d, up from 662 Mb/d in 2024 and 350 Mb/d in 2023.^Footnote 5 The increased capacity eased congestion across Canada’s oil pipeline network and enabled greater access to tidewater and overseas markets. Exports from the Westridge Marine Terminal surged, particularly heavy crude oil destined for Asia and the U.S. West Coast, marking a shift in Canadian oil export patterns.^Footnote 6 Apportionment remained at 0% throughout 2025, following years of apportionment on the system, although the Sumas delivery point was effectively full at certain periods in the year.^Footnote 7

Figure 3: Monthly throughput and available capacity on Trans Mountain Pipeline

Every quarter, major companies are required to report monthly pipeline throughput and available capacity data to the CER.^Footnote 8 This data is available quarterly on Open Government, Pipeline Profiles, and A look at pipeline flow and capacity.

Date modified:

2026-06-24