# HELOC Calculator: Home Equity Line of Credit Limit

> Your HELOC limit depends on home value and mortgage. Find the credit line you could get and the interest-only payment on what you use

On a $900,000 home with a $400,000 mortgage, a home equity line of credit could reach $320,000. Borrow $50,000 of it at 6.70% and you pay $279.17 a month in interest. Put in your own value, balance and rate to see where you land.

## How much can I borrow with a HELOC?

A HELOC is a revolving line secured by your home. You draw what you need, pay interest only on what you've used, and can borrow again as you pay it down. The Financial Consumer Agency of Canada says it plainly:

With a HELOC, you may borrow up to 65% of the value of your home.

Home equity lines of credit, [canada.ca](https://www.canada.ca/en/financial-consumer-agency/services/mortgages/home-equity-line-credit.html)
This calculator applies that 65% cap. It runs a second test as well: your mortgage plus the line must stay within 80% of the value. That lines up with the same FCAC page, which lists 20% as the minimum equity for a HELOC combined with a mortgage. Whichever result is smaller is your available amount. Your lender sets its own final limit, and some use tighter rules.

## What does the limit look like at different balances?

The first three rows use a $900,000 home and the last uses a $500,000 home, so you can watch the limit shrink as the mortgage grows.

| Home value | Mortgage balance | 65% cap | 80% less mortgage | Available |
| --- | --- | --- | --- | --- |
| $900,000 | $100,000 | $585,000 | $620,000 | $585,000 |
| $900,000 | $400,000 | $585,000 | $320,000 | $320,000 |
| $900,000 | $600,000 | $585,000 | $120,000 | $120,000 |
| $500,000 | $300,000 | $325,000 | $100,000 | $100,000 |

## A worked example

Take that $900,000 home with the $400,000 mortgage. The 65% cap is $585,000. Eighty percent of the value is $720,000, and once the mortgage comes off, $320,000 is left. The lower figure wins, so your line is $320,000, and here the 80% test is the one doing the limiting.

Plan to borrow $50,000 at 6.70% and the interest-only payment is $279.17 a month. Mortgage plus line then equal 50.0% of the value. Ask for $400,000 instead and the calculator warns you, then prices the interest on $320,000, which is $1,786.67 a month.

## What if the rate goes up?

Most HELOCs carry a variable rate, so the payment can move without you doing anything. Try two more points on the same $50,000, which makes 8.70%. Interest becomes $362.50 a month, up $83.33. That's manageable on a small balance, yet the same two points on a $320,000 draw would add over $500 a month. Test a higher rate in the box above before you borrow. A ballpark habit helps: multiply the amount you plan to draw by each point of rate change, then divide by 12, and you have the monthly swing. Lenders also differ on how they value your home, so a quote in writing beats a guess.

## What goes wrong with a HELOC?

The line is easy to use, and that's the risk. Treat the limit as a ceiling and not a target, and borrow only what you have a plan to repay. Interest also starts the day you take money out, so a draw you don't need is a cost from day one.

The payment shown is interest only, so no principal comes off and the debt stays where it is until you pay it down yourself. The calculator also uses the single rate you type in. Ask your lender what it really charges, then try a higher rate to see what the payment looks like under stress.

Home value is your own estimate here, and a lender may see it differently. Want to replace your mortgage instead of adding a line? Use the [mortgage refinance calculator](https://tax-services.ca/calculators/mortgage/mortgage-refinance). To weigh other borrowing, try the [line of credit calculator](https://tax-services.ca/calculators/loans-debt/line-of-credit) or the [personal loan calculator](https://tax-services.ca/calculators/loans-debt/personal-loan-calculator). And if the plan is to clear card debt, the [credit card payoff calculator](https://tax-services.ca/calculators/loans-debt/credit-card-payoff) shows how fast that goes.

## Where the numbers come from

The 65% cap and the 20% minimum equity for a HELOC combined with a mortgage come from the Financial Consumer Agency of Canada page quoted above. Your lender sets the rate, the value and the final limit. No government body has any tie to this site, and every result is an estimate.

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Source: https://tax-services.ca/calculators/mortgage/heloc-calculator
Last updated: 2026-10-07
Independent information site. Not affiliated with the CRA. No services, no guarantee of accuracy. See https://tax-services.ca/disclaimer