The performance reflects a steady recovery in Canada's oil and gas industry as rising oil prices encourage companies to restore production that they shut earlier in the pandemic.
Enbridge transported 2.6 million barrels per day (bpd) on Mainline in the second quarter, 7.5% higher than a year ago.
However, it moved less oil than it did in the first three months of the year, when it transported 2.75 million bpd.
The company had warned that scheduled maintenance for oil sands upgraders and refineries would be more concentrated between April and June than previously anticipated.
For the full year, Enbridge expects to transport 2.8 million bpd on average.
The Calgary-based company said it had formed an agreement with technology company Svante Inc and other firms to explore carbon capture opportunities.
Enbridge is talking with oil sands producers and other heavy industries about potential involvement, but needs clarity from the Canadian government on the tax credit it is developing, Executive Vice-President of Liquids Pipelines Vern Yu said on a call with analysts.
Enbridge expects full-year 2021 EBITDA and distributable cash flow to remain within its previously provided outlook of between C$13.9 billion ($11.1 billion) and C$14.3 billion and $4.70 to $5.00 per share, respectively.
Enbridge reported adjusted earnings of C$1.36 billion, or 67 Canadian cents per share, in the second quarter. That beat the average analysts' estimate of 57 Canadian cents, according to Refinitiv IBES.
Rival company TC Energy also beat estimates for quarterly profit on Thursday, as demand for its transport services returned with recovery in fuel prices.
($1 = 1.2438 Canadian dollars)
(Reporting by Arunima Kumar in Bengaluru and Rod Nickel in Winnipeg; Editing by Shailesh Kuber and Mike Harrison)