How much can you borrow with a HELOC in Canada?
A home equity line of credit (HELOC) can be as large as 65% of the home’s value at a federally regulated lender, and the mortgage plus the HELOC together cannot be more than 80% of the value. Whichever of those two rules gives the smaller number sets the maximum.
This HELOC calculator applies both rules to a home value and mortgage balance, then turns to the cost of borrowing: the interest-only payment on the amount borrowed, how many months a chosen monthly payment takes to clear it, and the total interest along the way. It is a home equity line of credit calculator built on the Canadian rules, not the United States ones that many calculators in the search results use. Lender pricing is on a separate page covering HELOC rates in Canada.
How to read this table: the first two rows cap what can be borrowed; the last two are the equity the Financial Consumer Agency of Canada says is needed to qualify. A lender can set lower limits.
| Rule | Limit | Measured against | Stated by |
|---|---|---|---|
| Revolving HELOC portion (the part that can be borrowed, repaid and borrowed again) | 65% | the value of the home | FCAC; OSFI Guideline B-20 |
| Mortgage and HELOC combined (any lending above the revolving limit must be amortized) | 80% | the value of the home | OSFI advisory on Guideline B-20; FCAC |
| Minimum home equity to qualify for a HELOC combined with a mortgage | 20% | the value of the home | FCAC |
| Minimum home equity to qualify for a standalone HELOC (more than) | 35% | the value of the home | FCAC |
Source: Home equity lines of credit — Financial Consumer Agency of Canada (page dated 2025-10-15); Home equity lines of credit — minimum equity to qualify (FCAC); Home equity lines of credit — home equity example (FCAC); Home equity lines of credit — variable rate based on prime (FCAC); Home equity lines of credit — risks (FCAC); Home equity lines of credit — notice of a rate change (FCAC); Borrowing against home equity — Financial Consumer Agency of Canada (page dated 2025-10-15); Guideline B-20: Residential mortgage underwriting practices and procedures (2017) — scope; Guideline B-20 — Home Equity Lines of Credit (HELOCs): 65 percent limit; Guideline B-20 — footnote 16: credit above 65 percent must be amortized; Clarification on the Treatment of Innovative Real Estate Secured Lending Products under Guideline B-20 (OSFI advisory, June 30, 2022) — 80 percent overall limit; OSFI advisory (June 30, 2022) — lending above 65 percent in a combined loan plan is non-readvanceable. In effect from October 31, 2017; checked October 11, 2026.
Who do the 65% and 80% rules apply to?
The 65% and 80% rules apply to federally regulated financial institutions: banks, and federally regulated trust, loan and insurance companies. They come from Guideline B-20 of the Office of the Superintendent of Financial Institutions (OSFI), which expects those lenders to limit the non-amortizing HELOC component of a residential mortgage to a loan-to-value ratio of 65 percent or less. A footnote to the guideline adds that more mortgage credit can be extended beyond that point, but the portion above the threshold should be amortized.
The overall ceiling comes from the legal maximum loan-to-value for uninsured mortgages. OSFI’s June 2022 advisory on combined loan plans, the regulator’s name for a mortgage with a readvanceable line of credit, says the overall limit of such a plan cannot exceed 80 percent, and that lending above the revolving limit should be amortizing and non-readvanceable.
Most credit unions are regulated provincially and follow their own regulator’s rules. Any lender, federal or provincial, can approve less than the maximum.
How do you use this HELOC calculator?
- Enter the home value. Use a realistic current value; a lender relies on an appraisal or the purchase price.
- Enter the mortgage balance. Use the amount still owing, or 0 for a mortgage-free home.
- Choose the type of HELOC. A HELOC combined with the mortgage (a readvanceable mortgage) or a standalone one.
- Enter the amount to borrow and the interest rate. The rate is the one in the lender’s offer or on the statement.
- Choose the repayment plan. Enter a monthly payment to see how long it takes, or a number of years to see the payment it needs.
- Open “Existing HELOC balance” if one is already open. A balance already owing uses up part of the limit and is added to the payment figures.
The four result cards show the maximum HELOC limit, the room available now, the interest-only payment and the payoff time.
What does a worked example look like?
Take a home worth $700,000 with $350,000 left on the mortgage. The owner wants to borrow $50,000 from a HELOC at 6.5% and pay $500 a month.
| Step | Amount | How it is worked out |
|---|---|---|
| Revolving cap | $455,000 | the HELOC portion alone |
| Combined cap | $560,000 | mortgage and HELOC together |
| Room under the combined cap | $210,000 | combined cap minus the mortgage |
| Maximum HELOC limit | $210,000 | the combined cap is the one that binds |
| Room left after borrowing | $160,000 | still available to draw |
| Interest-only payment | $270.83 a month | the balance never falls |
| First payment of $500 | $229.17 to principal | the rest is interest |
| Paid off in | 12 years, 1 month | 145 payments |
| Total interest | $22,210 | $72,210 repaid in all |
The owner in this example could draw far more than $50,000. The limit is a ceiling, not a target: the Financial Consumer Agency of Canada (FCAC) notes that lenders may approve a higher limit than a borrower needs, and that asking for a lower credit limit is an option.
How does the HELOC limit change as the mortgage is paid down?
The maximum HELOC limit a lender can set is one dollar higher for every dollar less owing on the mortgage, until the mortgage reaches 15% of the home’s value; from there the 65% revolving cap takes over and the maximum stops growing. The table shows the same $700,000 home at different mortgage balances.
| Mortgage balance | Share of home value | Room under the 80% cap | 65% revolving cap | Maximum HELOC limit |
|---|---|---|---|---|
| $560,000 | 80% | $0 | $455,000 | $0 |
| $490,000 | 70% | $70,000 | $455,000 | $70,000 |
| $350,000 | 50% | $210,000 | $455,000 | $210,000 |
| $210,000 | 30% | $350,000 | $455,000 | $350,000 |
| $105,000 | 15% | $455,000 | $455,000 | $455,000 |
| $0 | 0% | $560,000 | $455,000 | $455,000 |
Each row is the most a lender could authorize on a new approval at that mortgage balance. Whether the extra room shows up automatically depends on the type of HELOC and on how much is authorized in total. FCAC describes a HELOC combined with a mortgage as one where the available credit increases as mortgage principal is paid down, and a standalone HELOC as one where it does not.
OSFI’s June 2022 advisory narrows the first case. On a combined plan authorized above 65% of the home’s value in total, principal repaid on the part above 65% is expected to lower the overall limit, not free up HELOC room, until the whole plan is down to 65%. In the worked example the mortgage and the maximum HELOC add up to 80% of the value, so the first $105,000 of mortgage principal repaid would not add HELOC room by itself; a higher limit before then takes a new approval from the lender. The mortgage payment calculator shows how fast a mortgage balance falls, and the mortgage prepayment calculator shows the effect of extra payments on it.
How is the interest rate on a HELOC set?
The interest rate on a HELOC is usually variable and tied to the lender’s prime rate. In FCAC’s words, a variable HELOC rate is “typically based on your lender’s prime rate”, and its example is a rate of prime plus 1%: if the lender’s prime rate was 5.85%, the HELOC would have a rate of 6.85%. Those figures are FCAC’s illustration, not today’s rates. The margin above prime is negotiated with the lender, and FCAC notes that a lender may change a HELOC rate at any time; federally regulated institutions must give written notice within 30 days of a change.
Because the rate floats, the calculator asks for it directly and shows what a change would do. For the worked example, $50,000 at $500 a month:
| Rate | Interest-only payment | Paid off at $500 a month | Total interest |
|---|---|---|---|
| 5.5% | $229.17 | 135 months | $17,037 |
| 6.5% | $270.83 | 145 months | $22,210 |
| 7.5% | $312.50 | 158 months | $28,712 |
| 8.5% | $354.17 | 175 months | $37,283 |
Two points of rate add $15,073 of interest when the payment stays the same, because more of each payment goes to interest and less to the balance.
What is the interest-only payment, and why does it matter?
The interest-only payment is one month of interest on the balance: the balance times the annual rate, divided by 12. It matters because many HELOC agreements allow it as the regular payment, and a borrower who pays only that amount owes exactly the same balance years later.
In the worked example, the interest-only payment is $270.83 a month. Ten years of interest-only payments would cost $32,500 and leave the full $50,000 owing. Paying $567.74 a month instead clears the balance in the same ten years with $18,129 of interest. FCAC makes the same point in its guidance: a repayment schedule that includes more than the minimum payments may significantly reduce interest costs.
The calculator’s payment table compares the interest-only payment, the chosen payment, larger payments and the payments that clear the balance in 5, 10 and 15 years.
How does the maths work?
The calculator follows four steps, in plain English:
- Revolving cap. The home value is multiplied by the 65% revolving limit.
- Combined room. The home value is multiplied by the 80% combined limit, and the mortgage balance is subtracted. A negative result is treated as zero.
- Maximum limit and room. The smaller of the two is the maximum HELOC limit. Any balance already owing on the HELOC is subtracted to give the room available now.
- Interest and payoff. Each month, interest of the annual rate divided by 12 is charged on the balance. The monthly payment covers that interest first and the rest reduces the balance. The months are counted and the interest added up until the balance reaches zero, with the last payment trimmed to what is left.
When the monthly payment is not more than the first month’s interest, the balance cannot fall, and the calculator reports that it is never paid off instead of a payoff time. A payment only slightly above the interest is reported as taking more than 100 years, the longest payoff the calculator simulates. The same amortization maths runs the loan payment calculator, which also handles unsecured lines of credit and bi-weekly or weekly payments.
What risks does FCAC list for a HELOC?
FCAC gives five examples of the risks of a HELOC, and the calculator’s warnings are tied to them:
- If interest rates increase, repaying a HELOC may become hard, especially after withdrawing large amounts.
- If a HELOC is not paid back, the borrower could lose the home.
- A HELOC reduces the equity in the home, which may affect financial stability and limit future options when selling.
- The easy access to funds may tempt a borrower to take on more debt than can be paid back.
- Paying only the interest does not pay off the loan.
FCAC’s guidance is to consider these risks and have a repayment plan before taking out a HELOC: a clear objective, a budget, and a repayment schedule.
What are the most common mistakes with a HELOC calculation?
- Applying 65% to the equity instead of the home value. Both limits are percentages of the home’s full value, not of the equity.
- Forgetting the combined cap. With a large mortgage, the 80% rule is the one that binds, and the 65% figure overstates the limit.
- Treating the limit as the amount to borrow. Interest is charged on what is drawn, and a higher limit can tempt overspending.
- Budgeting on the interest-only payment. That payment never reduces the balance and rises whenever the rate does.
- Counting on the limit growing by itself. A standalone limit is fixed at approval, and on a combined plan authorized above 65% of the value, repaying mortgage principal lowers the overall limit first.
- Assuming a fixed rate. Most HELOC rates are variable; the rate table shows the payment at higher rates.
- Using US rules. Many online HELOC calculators use American loan-to-value limits and draw periods that do not match the Canadian rules above.
- Ignoring fees. Appraisal, legal, title search and discharge fees are not in the interest figures.
When is a different calculator or a professional the better next step?
A HELOC is one of several ways to borrow, and a different tool fits some questions better. For someone using a HELOC to consolidate other balances, the debt payoff calculator compares payoff orders across several debts. For a renewal coming up, the mortgage renewal calculator shows the payment at a new rate before more borrowing is added on top.
A mortgage broker or the lender can confirm the limit a specific institution will authorize, and a lawyer or notary is involved in registering the home as security. An independent financial planner can help when the borrowing is for investing, when retirement is close, or when the household budget is already tight. This calculator is an educational estimate, not financial advice; the lender’s written offer and disclosure statement are the final word on the limit, the rate and the fees.