The number that determines your real risk tolerance
Most “investment risk tolerance” questionnaires ask softball questions about how you’d feel if the market dropped 30 %. The actual answer is determined by how many months of runway sit in your HISA. A 30 % drawdown when you have 9 months of cash is an annoying paper loss; the same drawdown with 3 weeks of cash and a freshly laid-off household is the kind of forced sale that locks in losses for life.
Build it before you optimise it
The optimisation question — “should this be in a HISA, a money-market fund, a 1-year GIC, or a TFSA?” — comes after you have any emergency fund at all. For a household with $0 cash and $20,000 of consumer debt, the right move is usually to build a 1-month “starter” fund first, then aggressively pay down the debt while maintaining the floor, then top up to 3+ months once the debt is gone.
Self-employed runway is different
Freelancers and small-business owners need bigger buffers because their income has structural variance: invoicing lag (30–60 days), seasonal work, client turnover, and the fact that your “tax bill” isn’t deducted from each cheque the way it is for employees. A common mistake is including pre-tax revenue in “monthly income” — set aside 25–35 % for income tax, GST/HST, and CPP first, then count the remainder as actual take-home for runway math.