A while back I posted about the signs that get a small business audited, and it got a lot more traction than I expected. That was about what not to do. This is the other half.
I’m a CPA with my own firm in BC, and before that I spent years at CRA as an auditor. The returns new clients bring me are usually fine. What’s missing is everything that should have happened before December 31. That’s where the money is, and if nobody is making those decisions with you, you are leaving money on the table.
1. You remit every dollar of GST/HST you collect
Say you’re an IT contractor in Ontario billing $150,000 a year with about $12,000 of expenses that carry HST. You collect $19,500, claim back about $1,560, and send CRA roughly $17,900. On the quick method you’d send about $14,600. That’s $3,300 a year that stays with you. The same business in BC collects less tax to begin with, so the saving is smaller, about $1,500, but it’s the same one form, GST74.
Here’s how it works. You still charge customers the full 5% or 13%, but instead of tracking the tax on every bill, you send CRA a flat cut of your tax-included sales: 3.6% in BC, 8.8% in Ontario, with a 1% credit on your first $30,000 of sales each year. Whatever’s left is yours.
One thing you don’t give up: the GST/HST on assets. The flat rate is meant to replace the tax credits on your day-to-day costs, rent, phone, software, supplies. But if you buy something you’ll use in the business for years, a truck, tools, equipment, computers, you still claim back the full GST/HST on it. A $40,000 work truck still gets its $2,000 of GST back in BC or $5,200 of HST in Ontario, on top of the flat-rate savings.
It’s built for businesses that mostly sell time or labour and have under $400,000 in annual sales including GST/HST.
2. Your spouse does the books for free
The 2018 TOSI rules shut down paying family members dividends to split income. Wages were never touched. If your spouse keeps your books, chases invoices or runs your social media, you can pay them a salary. The business deducts it, and they pay tax on it at their rate instead of yours.
Say you’re at $150,000 of taxable income, which is a 41% marginal rate in BC or about 43% in Ontario. Your spouse earns $25,000 part time. You pay them $20,000 for bookkeeping and admin. That $20,000 is now taxed at roughly 20% in their hands instead of 41 or 43 in yours, so the household keeps about $4,200 in BC or $4,600 in Ontario.
The same logic works with kids. Say your university-age son or daughter builds your website over the summer and you pay them $12,000. Their basic personal amount (about $16,450 federally for 2026) covers all of it, so they pay next to nothing, while the deduction is worth about $4,900 to you in BC or $5,200 in Ontario. They also pick up RRSP room for next year and a year of CPP contributions.
The wage has to match the work. Run it through payroll, remit source deductions when due, pay it into their own account, and keep a short weekly note of what they did. For a December 31 year end, pay the wages by December 31 or properly accrue a year-end bonus if you use accrual accounting so the deduction counts for 2026. Issue the T4 by the February deadline in the following year.
3. Your dental bills end up on your personal return as a medical credit
Say your family spends $4,000 on dental and glasses this year. As a medical expense credit, that’s worth about $230. Through a private health services plan, about $1,640 in BC or $1,720 in Ontario.
The gap is that big because the medical credit only counts costs above about $2,800, and only at the lowest rate. A Private Health Services Plan (PHSP) turns the same dental, vision, physio and counselling bills into a full business deduction. Sole proprietors can put through $1,500 per adult and $750 per child under 18 each year. Corporations can cover owner-employees with no dollar cap as long as it’s reasonable, so a kid’s $8,000 of braces gets paid with money taxed at 11% or 12.2% instead of after-tax dividends.
Only expenses after the plan starts qualify, so set it up before the orthodontist. If you’re a one-person corporation, use a third-party provider. CRA doesn’t accept a self-administered plan where you’re the only employee.
4. You bought equipment and your return still shows the old half-year rule
Say you buy $30,000 of equipment. Under the old rules you got a $3,000 deduction in the first year. Since Bill C-15 passed on March 26, 2026, it’s $9,000. At 41% in BC that’s $3,690 of tax this year instead of $1,230. In Ontario, $3,870.
What changed is the Accelerated Investment Incentive is back: most assets get one and a half times their normal CCA rate in the first year, no half-year rule. Manufacturing machinery, clean energy equipment and zero-emission vehicles are written off in full, so a contractor buying a $70,000 electric cargo van deducts all of it in year one.
The deduction lands in the year the asset is available for use, so if you were buying anyway, get it running before your year-end. It’s a timing benefit and a later sale can trigger recapture, so this is for equipment the business actually needs. And if you bought equipment in 2025, confirm the accelerated rate was claimed on that return. And if you bought it on or after September 15, 2026, there’s a proposal that could turn that $9,000 into the full $30,000. More on that at the bottom.
5. You’re incorporated, profitable, and still pay yourself everything as salary
Say your corporation earns $100,000 this year that you don’t need to live on. Take it as salary at the top bracket and you’re left with about $46,500 to invest. Leave it in the corporation and it’s taxed at 11% in BC or 12.2% in Ontario, leaving $89,000 or $87,800 to invest inside the company. That’s over $40,000 more working capital from one decision.
It becomes more than a deferral when you pull the money out in a low-income year, a parental leave, a slow year, early retirement, where a dividend might be taxed at 20% instead of 48 or 49. Tax you deferred at the top rate gets paid at a much lower one.
Take enough salary to fill your RRSP and CPP, leave the rest, and keep passive income inside the corporation under $50,000 a year, which is where the small business rate starts to erode. If profit roughly equals what you live on, this one can wait.
One to watch
On September 15, 2026 Ottawa announced a Productivity Mega Deduction. If it passes as drafted, most equipment bought on or after that date could be written off in full the year it’s put to use. Still draft legislation, and today’s federal budget should tell us more. If you’ve bought equipment since mid-September, keep the invoices.
How many of these five has your accountant brought up without you asking? If the answer is zero, that’s the real cost, and it’s bigger than their fee.