Can I use the business's own cash to help pay for buying out my partner?

Often yes, but not without limits. A corporation can generally use its own funds, through a dividend, a share redemption, or the company itself purchasing the departing partner's shares, to help finance a buyout. Ontario corporate law includes solvency safeguards that restrict this, though: broadly, a corporation generally can't make this kind of payment if doing so would leave it unable to pay its debts as they come due, or would reduce its assets below its liabilities.

This means the specific mechanism matters — whether the remaining owner personally buys the shares and the company later pays a dividend to help fund it, or whether the company itself redeems or purchases the shares directly, since each has different tax and corporate-law consequences. Getting this structured correctly usually needs coordinated legal and accounting advice, both to make sure the solvency requirements are satisfied and to choose the most tax-efficient way of getting company funds into the buyout.