Deposit Interest in Canada: How Banks Calculate What You Earn

Deposit interest in Canada is the money a bank, credit union, or other deposit-taking institution pays you for holding funds in an account such as a savings account, chequing account, term deposit, or GIC. What you actually earn depends on the posted rate, how interest is calculated, how often it is paid, your balance, account fees, taxes, and whether the rate is promotional or ongoing.

This guide shows you how to estimate your earnings, compare accounts, and check whether the interest you receive matches the account terms.

Common Use Cases

• Emergency savings: You want accessible cash that earns interest without locking in funds.
• Short-term goals: You are saving for a trip, tuition, taxes, or a down payment within the next few months or years.
• Idle cash management: You have cash sitting in a low-interest chequing account and want to move it somewhere more productive.
• GIC or term deposit planning: You are considering locking in money for a fixed term in exchange for a predictable return.
• Promo rate evaluation: You want to know whether a temporary high rate is worthwhile after conditions, expiry dates, and transfer effort.
• Business cash reserves: You need to earn interest while keeping enough liquidity for payroll, taxes, or operating costs.

How Banks Usually Calculate Deposit Interest in Canada

Most deposit accounts use an annual interest rate, but the calculation often happens daily. A common approach is:

Daily interest = closing daily balance × annual interest rate ÷ number of days in the year

The daily amounts are then added up and paid according to the account terms, often monthly, annually, at maturity, or on another schedule. The exact method can vary by institution and product, so always check the account agreement.

Simple Interest vs. Compound Interest

• Simple interest: Interest is calculated only on the original principal. This is common in some term products, depending on how interest is paid.
• Compound interest: Interest is added to the balance, and future interest is calculated on the new higher balance. The more often it compounds, the more you may earn, assuming the same stated rate.

Posted Rate vs. Effective Return

The posted rate is the headline annual rate. Your effective return may be different because of compounding, promotional periods, tiered rates, fees, withdrawals, taxes, or days when the balance is lower.

Preparation Checklist

• Confirm the account type: savings, chequing, high-interest savings, GIC, term deposit, registered account, or business account.
• Write down the posted annual interest rate and whether it is fixed, variable, tiered, or promotional.
• Check how interest is calculated: daily balance, average balance, minimum monthly balance, or another method.
• Check how often interest is paid: monthly, annually, at maturity, or on a custom schedule.
• Identify fees that could reduce your net return, such as monthly account fees, transaction fees, transfer fees, or early redemption penalties.
• Check access rules: can you withdraw anytime, or is the money locked in?
• Confirm whether the deposit is eligible for deposit insurance through the relevant federal or provincial protection program.
• Decide whether the account is taxable or held inside a registered plan such as a TFSA, RRSP, RESP, or FHSA.
• Gather recent statements or expected balance amounts so your estimate is based on realistic cash flows.

Step-by-Step Workflow to Estimate What You Earn

1. Action: Identify the exact deposit product and read the interest section of its terms.

   Decision criterion: Continue only if you can confirm the rate type, calculation method, payment frequency, and access restrictions. If any of these are unclear, ask the institution before comparing returns.

2. Action: Determine your expected balance pattern.

   Decision criterion: Use a daily balance estimate if deposits and withdrawals will vary. Use a fixed principal estimate if the money will stay untouched for the full period.

3. Action: Convert the posted annual rate into a decimal for calculation.

   Decision criterion: If the rate is 4%, use 0.04 in the formula. If the rate is tiered or promotional, split the calculation by balance tier or time period.

4. Action: Estimate daily interest using the account’s stated method.

   Decision criterion: If interest is based on daily closing balance, calculate each day separately or use a stable average only when the balance does not change much.

5. Action: Add the daily interest amounts for the statement period or term.

   Decision criterion: If interest is paid monthly, total the days in that month. If it is paid at maturity, total the whole term and account for whether interest compounds or is paid out.

6. Action: Adjust for compounding if interest stays in the account.

   Decision criterion: If paid interest is added to the balance, include it in future interest calculations. If interest is paid to another account, do not compound it in the original deposit.

7. Action: Subtract account costs and penalties that apply to your planned use.

   Decision criterion: If fees or early withdrawal penalties would offset a meaningful part of the interest, compare a more flexible account or shorter term.

8. Action: Consider tax treatment.

   Decision criterion: If the account is non-registered, assume interest is generally taxable as income. If held in a registered plan, check the plan’s rules before treating the return as tax-free or tax-deferred.

9. Action: Compare the result with at least one alternative product of similar risk and access.

   Decision criterion: Choose the account that gives the best net return only if it also meets your liquidity, insurance, tax, and administrative needs.

10. Action: Recheck the actual interest posted after the first payment period.

    Decision criterion: If your estimate and the bank’s posted interest differ materially, review balance changes, rate changes, tier rules, payment dates, and fees before escalating the issue.

Example Calculation

Suppose you keep $10,000 in a savings account for 30 days at an annual interest rate of 3%, and the bank calculates interest on the daily closing balance.

Estimated daily interest: $10,000 × 0.03 ÷ 365 = about $0.82 per day

Estimated 30-day interest: about $0.82 × 30 = about $24.60 before tax and before any fees

If the balance changes during the month, the bank may calculate each day separately. If the rate is promotional for only part of the month, the calculation should be split between the promotional rate days and the regular rate days.

How to Compare Deposit Interest Offers

Quality Checks Before You Open or Renew an Account

• Rate check: Verify the rate directly in the account disclosure, not only in an advertisement.
• Promo check: Confirm when a promotional rate starts, ends, and what rate applies afterward.
• Balance check: Make sure your expected balance qualifies for the advertised tier.
• Fee check: Compare gross interest with any monthly or transaction costs.
• Liquidity check: Confirm you can access the money when you need it.
• Tax check: Estimate the after-tax return if the account is non-registered.
• Insurance check: Confirm the deposit type, ownership category, and institution are eligible for applicable protection.
• Statement check: After interest posts, compare it with your estimate and account activity.

Cautions and Common Mistakes

• Do not compare headline rates alone. A higher rate with fees, restrictions, or a short promotional period may produce less value than a lower ongoing rate.
• Watch tiered rates. Some accounts pay different rates on different balance portions or only after a balance threshold is met.
• Check whether interest is calculated on daily balance or minimum balance. A large withdrawal before the calculation date can reduce what you earn.
• Do not ignore tax. Interest in a non-registered account is generally taxable as income, which can reduce the after-tax benefit.
• Be careful with locked-in terms. A GIC or term deposit may pay more, but early access can be limited or costly.
• Confirm deposit protection rather than assuming it. Coverage can depend on the institution, account type, ownership structure, and deposit category.
• Review renewal instructions. Term deposits may renew automatically under terms that are different from what you would choose manually.

Practical Decision Rules

• Use a flexible savings account when you may need the money soon.
• Consider a redeemable or cashable term product when you want a rate commitment but still need some access.
• Consider a non-redeemable GIC only when you are confident you will not need the funds before maturity.
• Use registered accounts when they fit your broader tax and savings plan, not just because the posted rate looks attractive.
• Revisit variable-rate accounts regularly because rates can change.

Short FAQ

Is deposit interest in Canada calculated daily?

Often, yes. Many savings accounts calculate interest on the daily closing balance and pay it monthly, but the exact method depends on the product terms.

Why did I earn less interest than the advertised rate suggested?

Possible reasons include a promotional rate ending, a lower balance tier, withdrawals during the period, fees, a partial month, taxes, or interest being calculated differently than expected.

Is GIC interest calculated the same way as savings account interest?

Not always. A GIC may pay interest annually, at maturity, monthly, or on another schedule. It may use simple or compound interest depending on the product.

Do I pay tax on deposit interest?

Interest in a non-registered account is generally taxable as income. Interest earned inside a registered account depends on that plan’s rules.

Is the highest rate always the best choice?

No. The best choice is the highest suitable net return after considering access, fees, taxes, term length, deposit protection, and whether the rate is temporary.

How often should I review my deposit interest?

Review it whenever a promotional period ends, a term deposit matures, your balance changes significantly, or market rates have shifted enough to make alternatives worth comparing.