The clearest thing to come out of Canada's first investment summit is not a deal. It is a number. When Prime Minister Mark Carney announced the Productivity Mega Deduction on September 15 in Toronto, his government made a precise claim: the marginal effective tax rate on new business investment in Canada falls from about 13 percent to 6.4 percent, the lowest in the G7, below the 2026 U.S. rate of 16.9 percent and less than half the OECD average of 19 percent.
The mechanism behind that number is a permanent full write-off. Businesses can immediately expense 100 percent of the cost of eligible assets in the year they become available for use, covering machinery, manufacturing equipment, software, research and development, patents, fibre-optic cable, mining property, oil and gas pipelines, aircraft and vehicles. The measure expands Budget 2025's Productivity Super-Deduction, which covered roughly 15 percent of capital asset investment, to more than 65 percent, and applies to property acquired on or after the announcement date. The fiscal cost is about $36 billion over five years.
The deduction was one piece of a summit engineered around a stated goal of catalyzing C$1 trillion in investment over five years. Carney closed the event claiming nearly C$500 billion in commitments, while cautioning that many agreements take 12 to 18 months and not all are guaranteed. The largest named pledges included up to C$150 billion from TD over five years, more than C$100 billion from Scotiabank for Canadian businesses, C$70 billion from BMO over ten years, and a new C$50 billion "Maple Fund" from CPP Investments and Brookfield. A 66-page prospectus listed 167 projects, led by 63 mining and metals projects.
A tax argument, made in dollars
The government's case is that Canada lost the capital-cost recovery race to the United States and has been paying for it in deferred investment. Finance Minister François-Philippe Champagne called the measure "one of the most significant changes to Canada's business tax system in half a century." Candace Laing of the Canadian Chamber of Commerce called it "a moment we've been waiting for," while the Canadian Association of Petroleum Producers said it closes a significant competitive gap with the United States on expensing capital costs. The trucking industry's own effective rate, by one sector analysis, drops from 13.3 percent to negative 2.3 percent.
The timing is not accidental. Canada's business investment has declined for five consecutive quarters, the economy shrank in the first quarter of 2026, and more than 112,000 private-sector jobs have been lost since the start of the year. The longer arc is worse: private investment's share of GDP has fallen from about 25 percent to just over 20 percent, and an RBC analysis put the net outflow of capital at C$1 trillion over the past decade. The summit opened two days after the announcement that the Canada Revenue Agency will prioritize advance tax rulings for investments of C$1 billion or more, giving investors a binding decision on how tax law applies to a proposed transaction before they commit capital. Officials estimate economic activity gains of 1.4 to 3 times the federal cost, and up to 80,000 additional jobs a year a decade out.
The critics' ledger
The opposing case is that the package is expensive, tilted toward fossil fuels, and delivered behind closed doors. Greenpeace Canada's Keith Stewart called the tax breaks for fossil-fuel megaprojects "an act of climate vandalism." In Toronto, more than 1,000 people marched against the summit, with unions, Indigenous leaders and climate advocates criticizing fossil-fuel expansion, the lack of Indigenous consultation, and the privatization of public assets. The airport concessions announced alongside the tax measures, under which private operators would run Toronto Pearson, Vancouver, Montreal and Calgary airports with proceeds expected in the tens of billions, drew particular fire: critics argued that assets built with public money should not be sold to fund other priorities, and transport unions said workers were not part of the discussion.
There is also a smaller-bore skepticism that cuts closer to the mechanism itself. Tax professionals warned that prioritizing the largest advance-ruling requests will strain the CRA's capacity, with EY's Fred O'Riordan flagging the risk of crowding out other requests absent new resources. Financial Post columnist Jack Mintz argued Ottawa should "fix bad policy if Canada wants investment," and the Fraser Institute noted that 89 percent of the dollar value of Canadian energy exports still goes to the United States, which it reads as a sign that diversification remains aspiration more than reality. Some observers dispute the C$36 billion framing itself, arguing the figure is a timing effect rather than a permanent revenue loss. The government's multiplier estimates, like the C$1 trillion target, are projections, not commitments.
What the number does and does not settle
The 6.4 percent figure is a genuine policy change, not a slogan. Whether it converts into the investment supercycle the government describes depends on things a tax deduction cannot fix: permitting timelines, power costs, labor supply, and the resolution of the trade war that started the whole exercise. Ottawa's own materials cite mining projects that take more than 20 years from discovery to production, against about 13 in Australia, and regulatory delays that contributed to the cancellation of eight proposed LNG projects. The summit's answer to that was the Build Canada Strong Act and a "one project, one review, one year" approvals standard, plus a Major Projects Office with 27 initiatives representing C$500 billion in private opportunities. The tax change makes Canada's effective rate competitive with anyone's. The follow-through is now the test.
Whatever one thinks of the politics, the deduction has changed the arithmetic of investing in Canada, and both its supporters and its critics are right about something. Supporters are right that the country had become an outlier on capital-cost recovery and that a permanent, broad write-off was the fastest lever to pull. Critics are right that a C$36 billion tax change announced at a gala closed to the public deserves scrutiny rather than applause, and that the projects it is meant to attract, mines and pipelines chief among them, carry costs that do not show up in a marginal effective tax rate. The summit gave Canada a number it can sell. The next budget will show what it cost.
Primary sources
- Prime Minister's Office news release, "Prime Minister Carney introduces new Productivity Mega Deduction," for the deduction's scope, exclusions, the 13 to 6.4 percent METR claim, and the C$36 billion five-year cost.
- Canada Revenue Agency and Minister of Finance news release, "Greater tax certainty for major investments in Canada," for the C$1 billion-plus advance tax ruling commitment.
- The Canadian Press, "Business groups cheer Ottawa's tax deduction expansion," for business-group reaction and sector-level METR effects.
- AP News, coverage of the Canada Investment Summit, for Carney's pitch, attendance, and the C$1 trillion goal.
- National Observer, coverage of the Toronto protest, for the critics' stated grievances.