The "Tuesday Shrink": Why the 3.8% Inflation Spike Changes Your Borrowing Power Overnight

The "Tuesday Shrink": Why the 3.8% Inflation Spike Changes Your Borrowing Power Overnight

If you’re house hunting in Australia, you’re probably focused on finding the right place. But as you’ve been looking, the financial situation has just changed.

Yesterday, the Australian Bureau of Statistics (ABS) released important data showing that inflation is higher than expected. The Consumer Price Index (CPI) rose to 3.8% over the year to December.

This might sound like just numbers, but it has real and immediate effects for anyone with a mortgage pre-approval.

Here’s why this news could mean you have less to spend by next Tuesday.

The RBA’s Next Move: Tuesday, Feb 3

The Reserve Bank of Australia (RBA) has said it will do what’s needed to bring inflation back to its 2-3% target. With inflation still at 3.8%, many expect the RBA to raise the official cash rate at its meeting next Tuesday, February 3rd.

The expectation is a 0.25% hike, taking the cash rate to 3.85%.

For existing homeowners, this means a painful bump in monthly repayments. But for aspiring buyers, the impact is different and immediate. It’s about serviceability.

The "Hidden" Buffer: How Borrowing Power is Calculated

Many buyers assume that if the cash rate rises by 0.25%, their repayments will just cost a little more.

But lenders don't just calculate what you can afford today. By law, they must apply a "serviceability buffer," usually at least 3% above the actual loan rate, to ensure you won't go broke if rates rise in the future.

Here’s the catch: If the RBA raises rates next Tuesday, your lender’s base rate will also go up. That means the "buffered" rate they use to test you will increase as well.

As the test becomes tougher, the maximum amount you can borrow goes down.

The Impact: What Does a 0.25% Hike Look Like?

Everyone’s finances are different, but a 0.25% rate increase can make a big difference to how much you can borrow.

Let’s look at a hypothetical scenario:

  • Today (Thursday, Jan 29): You have a valid pre-approval for $800,000. At today’s rates, you pass the bank’s stress test.
  • Next Tuesday (Feb 3): The RBA raises rates by 0.25%. Lenders update their calculations.
  • Next Wednesday (Feb 4): Since the stress test is now tougher, your pre-approval might only be for $780,000, or even less, depending on your debts and income.

That is a potential $20,000 vanishing from your budget overnight, through no fault of your own.

Your 5-Day Action Plan

At Bheja.ai, we believe responsible lending means being transparent about risks. If you are actively looking to buy, here is how to protect yourself over the next few days:

1. Do NOT bid to your limit this Saturday. If you are attending an auction this weekend, do not stretch yourself to the absolute maximum of your current pre-approval letter. Leave yourself a safety margin. If you win the auction at your max limit on Saturday, and rates rise on Tuesday, you could face a very stressful formal approval process.

2. Check any older pre-approvals. If your pre-approval is over 30 days old, assume the numbers need updating. Call your broker or lender and ask them to check the figures with a possible rate increase in mind.

3. Ask the important question. Don’t just ask, "How much can I borrow?" Instead, ask, "If rates go up 0.25% next week, what’s my new maximum?" Make sure you know the lower number before making an offer.

Why Transparency Matters

We created Bheja.ai because we believe the mortgage process should be clear and open. In a changing economy, using old numbers isn’t just risky; it’s not responsible.

Whether you’re a borrower figuring out your real budget or a broker looking out for your clients, you need technology that not only calculates numbers but also anticipates changes.

Be careful in this market, and make sure your finances are checked against what could happen next week, not just today.

Pravin
Written by

Pravin Mahajan

Founder @ Bheja.ai | Mortgage Broker | Ex-CTO RateCity & CIMET

Pravin Mahajan is the Founder of Bheja.ai and an accredited Mortgage Broker (Credit Rep. 570637). Based in Sydney, he sits at the unique intersection of financial regulation and enterprise technology.

With over 30 years of experience, Pravin has architected the consumer platforms that millions of Australians rely on for daily financial and purchasing decisions. His career is defined by building high-scale systems that simplify complex choices:

  • RateCity (Acquired by Canstar): As Chief Product & Technology Officer, Pravin led the tech transformation that culminated in the company's acquisition. He orchestrated "Australia’s First Home Loan Sale," a digital initiative that reached over 12 million people.
  • CIMET: As CPTO, he built enterprise-grade infrastructure for energy and broadband comparison, scaling operations to support major B2B partners.
  • Salmat (Lasoo): He architected digital catalogue systems used by 5.7 million monthly users, digitising the retail experience for brands like Target and Myer.
  • Woolworths: Designed the real-time, secure "Pay at Pump" transaction infrastructure deployed Australia-wide.

Today, at Bheja.ai, Pravin combines this deep technical background with his Certificate IV in Finance and Mortgage Broking to build AI agents that don't just compare loans, but help Australians actively secure their financial future.