How the US–Iran War Is Pushing Mortgage Rates Higher — and Why Ontario Homeowners Need to Act Now

Two weeks ago, the world changed. On February 28, 2026, the United States and Israel launched coordinated air strikes against Iran, marking the beginning of an armed conflict that has already reshaped global energy markets, rattled bond markets, and — for Ontario homeowners and buyers — started pushing mortgage rates in a direction nobody wanted them to go.

If you have a mortgage renewal coming up in the next 120–180 days, or you're planning to buy or refinance a home in Ontario, this post is for you. I'm going to explain exactly what's happening, why it matters to your mortgage, and what you should do about it — starting today.

What Happened: The US–Iran Conflict in Brief

On February 28, 2026, the United States and Israel carried out a series of air strikes against targets in Iran. The conflict escalated quickly. Iran responded by effectively closing the Strait of Hormuz — the narrow waterway through which roughly 20% of the world's oil supply flows every single day.

The market reaction was immediate. Brent crude oil surpassed $90 per barrel within days and has since pushed past $100 per barrel. Global shipping routes have been disrupted. Energy costs are spiking. And bond markets around the world are repricing risk in real time.

For most Canadians, a conflict in the Middle East can feel far away. But when it comes to your mortgage, the consequences are arriving at your doorstep right now.

Why Bond Yields Are Rising (Not Falling) During a War

If you follow financial news, you might be wondering: doesn't war usually cause investors to rush into safe-haven assets like government bonds, pushing yields down?

Normally, yes. But this conflict is different — and understanding why is critical to understanding what's happening to mortgage rates.

The closure of the Strait of Hormuz has created an inflationary oil shock. Oil above $100 per barrel feeds directly into transportation costs, manufacturing costs, heating costs, and eventually into the price of virtually everything consumers buy. That inflationary pressure is doing something unusual: it's outweighing the traditional flight-to-safety demand for government bonds.

In simple terms, investors are more worried about inflation eating away at their bond returns than they are eager to buy bonds for safety. The result: bond yields are going up, not down.

Bond Yield & Rate Movement Since the Conflict

The key figure in that table for Ontario mortgage holders is the Canada 5-year bond yield. At 3.03%, it's at its highest level since late 2024. The Bloomberg Global Aggregate Bond Index has erased its gains for all of 2026 — the global bond rally that started last year has completely reversed.

What This Means for Ontario Homeowners

Let me break this down by where you sit in the mortgage lifecycle, because the impact and the urgency are different depending on your situation.

If Your Renewal Is Coming Up in 120–180 Days

This is the group I'm most concerned about. If your mortgage is up for renewal this summer or early fall, the rate you'll be offered at renewal depends on where bond yields are at that time. And right now, the trend is unmistakably upward.

Here's the math that matters: on a $500,000 mortgage balance, a 0.25% increase in your renewal rate costs you approximately $73 more per month — or $4,380 over a 5-year term. If rates climb another 0.25% before you renew, that doubles to $8,760 in additional interest over five years.

Most lenders will allow you to lock in a rate 90–120 days before your renewal date at no cost. Some brokers — including our firm — can negotiate early rate holds of up to 150 days with certain lenders. If your renewal falls anywhere between June and September 2026, you can secure today's rate right now and protect yourself from further increases.

If You're Looking to Purchase a Home in Ontario

For buyers, rising fixed rates change the math on two fronts. First, your monthly payment goes up. Second — and this is the one most people miss — your qualifying amount goes down.

Under the federal stress test, you qualify at either your contract rate plus 2% or 5.25%, whichever is higher. When fixed rates climb, your stress-tested qualifying rate climbs with them, which means the maximum mortgage amount a lender will approve you for actually shrinks. A 0.25% increase in the fixed rate can reduce your purchasing power by $10,000–$15,000.

If you're house-hunting this spring, getting pre-approved now accomplishes two things: it locks in today's rate for your purchase, and it locks in today's higher qualifying amount before it potentially drops further.

The Ontario market is still in a buyer-friendly cycle — elevated inventory, stable prices, negotiating power. But the rate window is narrowing. The combination of a buyer's market and still-reasonable rates may not last if this conflict drags on.

If You're Considering a Refinance

Refinancing is rate-sensitive by definition — you're restructuring your existing mortgage to take advantage of better terms, consolidate debt, or access equity. Every basis point increase in the fixed rate changes the breakeven calculation on whether a refinance makes financial sense.

If you've been thinking about refinancing to consolidate high-interest debt, access home equity, or switch from variable to fixed, the window is getting smaller. At current rates, refinancing still makes strong financial sense for many homeowners — particularly those carrying credit card or line-of-credit debt at 8–20% interest. But if fixed rates climb another 25–50 basis points over the coming weeks, the savings margin tightens.

My recommendation: run the numbers now. We can tell you in one conversation whether a refinance saves you money at today's rates, and if it does, we can lock in that rate while you complete the process.

What About the Bank of Canada?

The Bank of Canada's next interest rate announcement is March 18, 2026 — less than a week away. The overnight rate currently sits at 2.25%, and most economists expect a hold at this meeting.

But here's what's shifted: before the conflict, markets were pricing in potential rate cuts later in 2026. Now, with oil-driven inflationary pressure, that narrative has reversed. Several economists have begun pricing in the possibility of rate hikes by Q4 2026 if the conflict persists and oil stays elevated.

The critical point here is that both fixed and variable rates face upward pressure. Fixed rates are already climbing because of bond yields. And if the Bank of Canada is forced to raise the overnight rate to combat inflation, variable-rate mortgage holders will feel the impact immediately through higher prime rates.

Your Action Plan: What to Do This Week

I don't say this to create urgency for urgency's sake. I'm saying it because the data supports it. Every week that passes with oil above $100 and bond yields trending upward is a week where the rate you could have locked in gets more expensive.

Renewing in 120–180 Days

1. Call your broker today — not your current lender. Your bank's retention team will offer you posted rates. A broker compares 40+ lenders to find the lowest rate available.
2. Get a rate hold immediately. This freezes today's rate for 90–120+ days at zero cost. If rates drop, you renegotiate. If rates rise, you're protected.
3. Don't wait for your renewal letter. By the time your lender mails you an offer 21 days before maturity, rates may have climbed significantly. Starting early gives you leverage and options.

Purchasing a Home

1. Get pre-approved now to lock in today's rate and qualifying amount. Every rate increase reduces how much home you can afford.
2. Move quickly on offers. The Ontario market still has elevated inventory, which means you have negotiating power on price. Don't let a rate increase erode the savings you're getting on the purchase.
3. Consider the 30-year amortization if you're a first-time buyer. Lower monthly payments give you a cushion against rate uncertainty.

Considering a Refinance

1. Run the numbers this week. A 15-minute conversation can tell you if refinancing saves you money at today's rates.
2. Consolidate high-interest debt now. If you're carrying $30,000+ on credit cards at 20% interest, rolling that into your mortgage at 4% saves you real money — but only if you lock in before rates climb further.
3. Lock in a rate while you decide. A rate hold gives you time to think without the pressure of rates moving against you.

The Bottom Line

The US–Iran conflict has created an oil-driven inflationary shock that is pushing bond yields — and by extension, fixed mortgage rates — higher across Canada. The Bank of Canada's overnight rate at 2.25% is expected to hold for now, but the risk of future hikes is growing. Variable rate holders are not immune either.

For Ontario homeowners approaching renewal in the next 120–180 days, this is a moment that demands action — not panic, but deliberate, informed action. Lock in a rate hold. Start the conversation with a mortgage professional. Compare your options across multiple lenders.

For buyers, the Ontario market still offers favourable conditions: inventory, negotiating power, and programs like the 30-year amortization and FHSA. But the rate side of the equation is deteriorating week by week. Getting pre-approved today protects both your rate and your purchasing power.

For those considering refinancing, the math still works at today's rates for most scenarios — but the window is narrowing. If the conflict persists and oil stays above $100, the rates you'll see in 60–90 days will almost certainly be higher than what's available today.

Geopolitical events are outside your control. Your mortgage rate doesn't have to be.

Amit Mistry is the Principal Broker at Newcastle Financial Corporation (FSRA Licence #13522), serving homeowners and buyers across Toronto, the GTA, and all of Ontario. If you have questions about how the current rate environment affects your mortgage, call (647) 646-6523 or book a free consultation.