How to Calculate HISA Interest
Canadian banks work out your interest every day and pay it once a month. Here is the formula, a worked example, and what promo rates really pay over a year.
Rates updated October 22, 2026.
Interest calculator
- Per day
- $0.96
- Per 30-day month
- $28.77
- After 1 year
- $355.67
Assumes the rate stays the same and interest is paid monthly. Before tax.
The formula
Nearly every Canadian bank and credit union uses the same two steps:
- Each day: balance × interest rate ÷ 365
- Each month: add up the daily amounts and deposit them into your account
Interest is based on your balance at the end of each day. Money you deposit starts earning that day, and money you withdraw stops earning that day.
Because the monthly payment is added to your balance, next month's interest is a little higher. That is compounding. Since it's a daily calculation, a 31-day month pays slightly more than February.
Example: $10,000 at 3.50%
3.50% is today's highest regular (non-promo) rate, from KOHO.
- Per day: $10,000 × 3.50% ÷ 365 = $0.96
- In a 30-day month: $0.96 × 30 = $28.77
- Over 12 months, with each payment added to your balance: $355.67
Do promo rates pay more?
Many banks advertise a high rate for a few months, then drop to a much lower base rate. Here is $10,000 over one year with a typical promo (4.60% for 5 months, then 0.30%) compared with a steady 3.50%.
| Period | Promo account | Steady 3.50% |
|---|---|---|
| Months 1–5 | $193.14 | $146.69 |
| Months 6–12 | $17.85 | $208.98 |
| Total for the year | $210.99 | $355.67 |
| Average rate | 2.09% | 3.50% |
If you leave your money in place, the steady account pays about $145 more. A promo only wins if you move your money to a new promo when it ends.
Interest on $5,000 to $100,000
At 3.50%, paid monthly.
| Balance | Per day | Per month | 1 year | 5 years |
|---|---|---|---|---|
| $5,000 | $0.48 | $14.38 | $177.83 | $954.71 |
| $10,000 | $0.96 | $28.77 | $355.67 | $1,909.43 |
| $25,000 | $2.40 | $71.92 | $889.17 | $4,773.57 |
| $50,000 | $4.79 | $143.84 | $1,778.35 | $9,547.14 |
| $100,000 | $9.59 | $287.67 | $3,556.70 | $19,094.28 |
Is HISA interest taxed?
Yes, unless the account is a TFSA or RRSP. Interest is fully taxed at your marginal rate, unlike capital gains or Canadian dividends, which get a break.
- Your bank sends a T5 slip if you earn $50 or more in a year. You still have to report smaller amounts on line 12100.
- Example: $1,000 of interest at a 35% marginal rate leaves you $650 after tax.
- In a TFSA, the interest is tax-free and you don't report it.
HISA or GIC?
A HISA lets you take your money out any time, but the rate can change whenever the bank decides, often after a Bank of Canada announcement. A GIC locks your rate for 1 to 5 years, but your money is tied up until it matures.
Compare fixed rates with the GIC calculator, or split your savings across terms with the GIC ladder calculator.
Frequently Asked Questions
How much interest does $10,000 earn in a HISA?
At 3.50%, $10,000 earns about $0.96 a day, $28.77 in a 30-day month, and $355.67 over a year.
When is HISA interest paid?
Most Canadian banks, including EQ Bank, Tangerine, Simplii, Scotiabank and TD, calculate interest daily and pay it on the last day of each month.
How much interest does $50,000 earn in a HISA?
At 3.50%, $50,000 earns about $4.79 a day, $143.84 in a 30-day month, and $1,778.35 over a year.
How much interest does $100,000 earn in a HISA?
At 3.50%, $100,000 earns about $9.59 a day, $287.67 in a 30-day month, and $3,556.70 over a year.
Is my HISA protected by CDIC?
Yes, at CDIC member banks, eligible deposits are covered up to $100,000 per category. Credit union deposits are covered by provincial insurers instead.