The Interest Deduction a Kitchener Buyout Almost Lost to Speed

The situation

What worried Mehrdad was not whether the deal would close. It was the thought of a letter arriving three or four years later, after the acquisition had been folded into daily operations and everyone had stopped thinking about how it was financed, telling the company that a large share of the interest it had been deducting all along was not deductible after all, with penalties and interest of its own stacked on top. He had seen that kind of reassessment sink the margins on a deal before, at a previous fund, and he did not want to explain it to his investment committee a second time.

Mehrdad had spent his early career as a welder before moving into operations for a private equity fund that specialized in buying mid-size Canadian manufacturers, and he now managed the fund's Ontario portfolio companies day to day. Darius, who had trained as an HVAC technician before becoming the fund's finance lead for Canadian acquisitions, was running point on how this particular deal would actually be paid for. The target was a Kitchener metal fabrication business generating steady contract revenue, being sold by its founder, Lucia, for a price in the $15 to $30 million range.

The fund's US parent company had cash sitting in the United States and wanted to fund most of the Kitchener purchase with an intercompany loan from the US parent directly to the Canadian acquisition entity, rather than routing new equity or third-party debt into the deal. On paper, that was the cheapest and fastest way to get the money into Canada: no bank underwriting, no external lender due diligence, no delay waiting on a credit committee that had never dealt with this borrower before. Mehrdad and Darius wanted to sign the intercompany loan on the terms the US parent's finance team had already drafted, close within three weeks, and move on to integration.

The draft loan terms, however, had been put together by a US finance team unfamiliar with how Canadian tax rules treat debt owed by a Canadian company to a related non-resident lender. Nobody on the US side had asked whether the loan, as structured, would actually let the Canadian acquisition entity deduct the interest it planned to pay every year going forward, and nobody on the Canadian side had yet been asked to check.

What the review found

Canadian tax law limits how much debt a Canadian company can owe to a related non-resident shareholder or affiliate, like a US parent, before the interest on that debt stops being deductible for Canadian tax purposes. The rule compares the company's related-party debt to its equity, and once that ratio crosses the threshold the legislation sets, interest on the excess portion is no longer deductible against the Canadian company's income. The draft loan terms from the US parent's finance team would have funded roughly three-quarters of the purchase price through the intercompany loan, using only a thin layer of equity underneath it, well past the point where the excess interest would stop being deductible.

That mattered enormously to the deal's underlying economics. Interest deductibility is what makes debt financing cheaper than equity in the first place, because deductible interest reduces the company's taxable income every year the loan is outstanding. If a meaningful share of the interest on this loan were non-deductible from day one, the acquisition would be paying financing costs without getting the tax benefit that had been built into the fund's return projections, for as long as the loan remained outstanding at that ratio. Worse, if the structure were set up to look compliant at closing but drifted over the ratio as the company's equity base changed over time, a future audit could challenge years of deductions retroactively rather than just going forward, which is exactly the letter Mehrdad had described being afraid of.

There was a second issue layered on top. Interest paid by a Canadian company to a related non-resident lender is also generally subject to Canadian withholding tax, deducted before the payment leaves the country, unless the loan terms and the relationship between the parties qualify for a reduced rate under the applicable treaty. The draft terms had not addressed withholding tax at all, which meant the US parent was likely to receive less than it expected on every interest payment, or the Canadian entity would need to gross up payments to compensate, either of which changed the deal's real cost in ways nobody had modelled.

None of this was visible from the numbers the US finance team had circulated, because those numbers assumed the interest would simply flow as a deductible expense every year, the way it would under US rules for a comparable domestic loan. The mismatch was not a drafting error so much as a difference in what each country's tax system allows related parties to do with intercompany debt, and it was the kind of gap that rarely gets caught until a Canadian tax specialist looks at the actual structure rather than the term sheet's summary, by which point, without a review like this one, the loan would already have been funded.

What we did

1. Modelled the actual debt-to-equity ratio the draft loan would create. We built out the acquisition entity's balance sheet as the deal was actually structured, not as assumed, and confirmed the intercompany loan as drafted would push related-party debt well past the point where a meaningful share of the annual interest would lose its deductibility. This gave Mehrdad a concrete number, not a general warning, to bring back to the investment committee.
2. Explained plainly why speed was creating the exposure, not the loan itself. Mehrdad and Darius initially pushed back, wanting to close on the original timeline and deal with structuring questions afterward. We walked through, in plain terms, why a thin capitalization problem cannot be fixed retroactively once the loan is in place and the money has moved, because the ratio is tested against how the deal was actually financed at the relevant times, not against what the parties later wished it had looked like.
3. Rebuilt the financing mix to bring the ratio inside the safe range. We worked with the fund's finance team to reduce the size of the intercompany loan and increase the equity contribution from the US parent correspondingly, which cost the fund more up front in committed capital but kept the debt-to-equity ratio comfortably within the limit the legislation sets, protecting the interest deduction going forward.
4. Reviewed the loan terms for withholding tax treatment. We confirmed the rate of withholding tax that would apply to interest payments under the loan as restructured, checked whether the US parent qualified for treaty relief on that rate, and built the actual after-withholding cost into the fund's return model so the numbers going to the investment committee reflected reality rather than an unexamined assumption.
5. Added a covenant requiring the ratio to be monitored annually. Because the Canadian entity's equity base could change over time as profits were retained or distributed, we built in an annual check of the debt-to-equity position, so a drift toward the limit years down the road would be caught and corrected before it became a retroactive problem rather than after.
6. Delivered a short summary memo the fund could use with its own investment committee. Rather than a lengthy technical opinion nobody outside the tax group would read in time, we prepared a concise explanation of the risk, the fix, and the added upfront equity cost, in plain language a non-tax-specialist committee could act on quickly, since the closing timeline, while extended by the restructuring, was still genuinely tight and the committee needed to approve the added capital within days, not weeks.
7. Coordinated directly with the US parent's finance team on the revised terms. Rather than simply hand back a list of problems, we worked with Darius to walk the US team through why Canadian rules required a different approach than their usual domestic financing template, so the revised structure could be built into their process for future Canadian acquisitions, not just patched for this one deal.

The outcome

The deal closed roughly five weeks later than the original three-week target the US parent's finance team had wanted, because raising the additional equity contribution required a further round of internal approvals on the US side. That delay was a real cost, both in Mehrdad's time managing an anxious investment committee and in the fund's committed capital, which now sat as equity rather than the cheaper debt originally planned.

What the fund avoided was larger and further out. Had the deal closed on the original financing terms, the acquisition entity would likely have been carrying several years of partially non-deductible interest by the time anyone noticed, on a loan sized in the tens of millions, with the corresponding tax reassessment, penalties, and interest arriving well after the fund had stopped focused on this particular file. Mehrdad's fear, the letter years later, was not hypothetical; it was the ordinary outcome of the structure the US team had drafted.

This was not, in the end, a story where everything went the fund's way. It gave up the fast, cheap close it had wanted, and it committed more capital upfront than the original plan called for. But the loss was contained to a known, budgeted cost taken deliberately at closing, rather than an open-ended tax exposure discovered years later with no good way to fix it retroactively. Mehrdad's committee approved the revised structure without much argument once the numbers were in front of them, which was, in its own quiet way, the outcome the file had been steering toward from the first review.

Mehrdad later said the harder conversation was not with his own committee but with the US parent's finance team, who had assumed their standard financing template would simply work in Canada the way it had on prior acquisitions in other countries. Getting them to accept that Canadian thin capitalization rules required a genuinely different structure, not a minor adjustment, took more persuading than the legal analysis itself. That conversation, uncomfortable as it was, is now part of how the fund approaches every Canadian acquisition it finances from its US parent going forward.

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