Glossary · Australian property
Mortgage stress.
When more than 30% of a household's gross income goes to mortgage repayments. ABS and AHURI use the threshold to identify financial distress. APRA monitors the 30+% cohort as a leading indicator of arrears and forced sales.
Definition and threshold: the 30/40 rule (housing-stress framework, AHURI). If the bottom 40% of households by income spend more than 30% on housing, it's housing stress. Mortgage stress is the homeowner-side variant, applied to all income deciles. Some lenders and analysts use a tighter threshold (35-40%) for severe stress.
Drivers: rate hikes (largest single driver in 2022-24), declining real wage growth, inflation in non-discretionary categories (utilities, groceries, childcare), divorce / separation reducing household income, illness / unemployment.
Warning signs at the household level: skipping non-mortgage bills to make repayments, drawing on credit cards or BNPL for groceries, missing extras (insurance and super contributions), constantly checking offset balance and leaning on it for cashflow. ASIC MoneySmart's hardship-program directory is the right escalation when stress crosses to inability to pay. Most lenders offer 3-6 month repayment pauses or rate-cut concessions before any default.
Why track it: mortgage stress in a suburb is a leading indicator of forced-sale supply 12-24 months later. Suburbs with 30+% mortgage stress tend to underperform on capital growth and correct first when broader market softens.
Worked example
Household gross income $130K. Mortgage $5,200/month = $62,400/year. Mortgage-to-income = 48%, well into severe stress. The same household at $200K gross would be at 31%, borderline stress. The same loan at 4% (vs 6.5%) would be ~$3,800/month = 35%, borderline. Each lever is independent.
Source
AHURI - housing affordability + mortgage stress research; ABS Survey of Income and Housing; ASIC MoneySmart hardship guidance.
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