Loan terms explained: principal, interest and amortisation

Loan terms explained, plainly: principal is the money you actually borrowed, interest is the rent you pay on it, and amortisation is the timetable that decides how each payment splits between the two. Read a loan document with those three ideas in hand and the rest — term, rate, payment frequency, prepayment rules — falls into place.

First, a note on who is talking. LoanGoose is a loan matching and comparison service, not a lender. We don't issue loans, set rates or decide who qualifies. What we can do is explain how the pieces fit together in Canada, so you can walk into a conversation with a lender knowing what you're looking at.

Principal: the balance that actually shrinks

Principal is what you owe before interest is layered on top. On a standard instalment loan it starts as the amount advanced to you and drops with every payment you make. On a revolving product such as a line of credit, principal moves in both directions: draw more and it climbs, pay it down and it falls.

The size of the principal a lender is willing to advance depends on your income, your existing debts and your credit history, among other things. The Financial Consumer Agency of Canada walks through how personal loan applications are assessed and what lenders look at — see FCAC — personal loans. A useful habit: whenever a lender quotes you a monthly payment, ask what the principal balance will be after the first year. That one question exposes a lot.

Interest: the price of borrowing, and how it compounds

Interest is a rate applied to the outstanding principal over time. Two loans can carry the same headline rate and still cost very different amounts, because what matters is how often interest is calculated and added to the balance.

In Canada, fixed-rate mortgages are compounded semi-annually by law. That's a quirk worth knowing when you compare a mortgage quote to a personal loan quote, because the two aren't calculated the same way. The FCAC — mortgages page covers how mortgage rates and payments work, including the gap between the rate you're quoted and the rate you effectively pay.

Rates move over time. The Bank of Canada publishes the policy and market rates that sit behind a lot of consumer borrowing costs — see Bank of Canada — rates — though the rate you're offered is a business decision made by the lender, not a published number you're entitled to.

You'll see two kinds of interest named on almost every offer:

• Fixed — the rate stays put for the term. Your payment is predictable, and so is the total cost.
• Variable — the rate moves with an underlying benchmark. Either your payment or your amortisation period absorbs the change, depending on the contract.

Variable isn't automatically cheaper. It's a bet on direction, and you're the one holding it.

Amortisation: the schedule behind the payment

Amortisation is the plan for paying off principal and interest over a set number of payments. On an amortising loan each payment is the same size, but its ingredients change. Early on, most of the payment covers interest because the balance is large. Later, most of it goes to principal because the balance is small. The payment feels static; what it's doing quietly shifts.

Stretch the amortisation period and each payment gets smaller — but you pay interest for longer, so the total cost climbs. Shorten it and the reverse happens. That trade-off is the whole game. It's why "what's the monthly payment?" is the wrong first question. The better one is "what will this cost me in total?"

One warning label: if a payment doesn't even cover the interest being charged, the balance grows instead of shrinking. That's negative amortisation, and it's a trap in disguise.

The vocabulary, decoded

What Canadian law puts a ceiling on

There is an outer limit. The Criminal Code sets the criminal rate of interest at 35% per year under section 347, calculated by a defined method that aggregates interest and certain charges — see Criminal Code s. 347 — criminal rate of interest.

Payday lending sits in its own lane. Where a province runs a licensed payday lending regime, federal regulations cap the cost of borrowing at $14 per $100 advanced — the Payday Lending Regulations, SOR/2024-114 — and a province may set a lower cap, in which case the lower figure applies. A payday loan is generally up to $1,500 for a term of 62 days or less. Quebec doesn't license payday lending, which effectively prohibits the model there. The FCAC — payday loans page lays out the federal side.

Secured borrowing changes the arithmetic

A secured loan is tied to an asset, usually your home or your vehicle. Because the lender can recover something if you default, secured borrowing often costs less than unsecured. But the risk moves to you, because the asset is on the line.

At federally regulated lenders, a home equity line of credit is generally limited to 65% of appraised property value, with total secured lending usually capped at 80%. Mortgage underwriting follows OSFI Guideline B-20 — residential mortgage underwriting, under which federally regulated lenders generally work to a total debt service ratio ceiling of about 44% and apply a qualifying stress-test rate above the contract rate. Translation: you may qualify for less than the sticker math suggests.

A short checklist before you sign

• Ask for the total cost of borrowing, not just the payment.
• Ask whether the rate is fixed or variable, and what triggers a change.
• Ask what the prepayment rules are, and whether paying early saves you anything.
• Ask what happens if you miss a payment — fees, penalties, credit reporting.
• Ask whether the loan is secured, and if so, against what.
• Read the amortisation schedule itself, not just the summary page.

When borrowing is the wrong move

If the loan is covering a gap that will still be there next month, more debt usually deepens the hole. Same if you're borrowing to make payments on existing debt without a plan to change the underlying budget. And if a lender rushes you, waves off your questions, or won't put the numbers in writing, that's your cue to leave.

If you're already struggling, the tools are different. A consumer proposal stays on your credit report for three years after completion, or six years from filing, whichever comes first. A first bankruptcy stays on for six years after discharge. Only a licensed insolvency trustee can administer either — the Office of the Superintendent of Bankruptcy Canada regulates them. For decisions that big, talk to a licensed professional who can see your whole picture.

Routine credit hygiene helps too. Canada has two national credit reporting bureaus, Equifax Canada and TransUnion Canada, and a free copy of your credit report is available from each — see FCAC — credit reports and scores. Knowing what's on your file before you apply beats finding out afterwards.

If something goes wrong with a federally regulated financial institution, consumer complaints are handled by the FCAC — complaints. Provinces license and supervise most other lenders, and each province has a consumer protection office — the FCAC — provincial and territorial regulators page lists them. Knowing who supervises your lender is part of knowing what you're signing.

The short version

Principal is what you owe. Interest is what it costs to owe it. Amortisation decides how fast you get out. Understand those three and you can compare almost any two loan offers without a finance degree — and you'll spot the expensive ones early.

LoanGoose is a loan matching and comparison service, not a lender. The lowest rates are only available to the most qualified applicants.