What is a good debt-to-income ratio?

The short answer

The numbers most commonly cited — 28% for housing, 36% for total debt, 43% as a hard ceiling — are not personal finance laws. They are regulatory underwriting thresholds, designed for mortgage approval, not for individual financial health.

The 43% figure comes from the Qualified Mortgage (QM) rule established by the Consumer Financial Protection Bureau in 2014. It defines the maximum back-end DTI a lender can use while still benefiting from QM safe harbor protections. Outside that regulatory frame, a “good” DTI depends on income stability, savings cushion, and the rate environment.

What changed after 2022 is the binding nature of the constraint. With Federal Funds rate up 525 bp between March 2022 and July 2023, the same household income now services a meaningfully higher debt payment for the same nominal balance.

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What the data shows

U.S. household debt reached record levels in late 2025 according to the New York Fed Household Debt and Credit Report.

The contextual figures (NY Fed, Q4 2025):

• Total household debt: $18.36 trillion, up from $17.94 trillion in Q4 2024
• Mortgage balances: $13.17 trillion, with $524 billion newly originated in Q4 2025
• Auto loan balances: $1.67 trillion, up 56.7% over the past decade
• Aggregate delinquency: 4.8% of outstanding debt in some stage of delinquency

The Federal Housing Administration documents that the share of FHA borrowers with back-end DTI above 43% rose from approximately 25% in 2010 to over 50% by 2023 — the regulatory threshold became less of a screen as it was widened by the QM Patch.

→ Dataset: U.S. household debt to GDP

Why it happens — the macro mechanism

Three forces shape what makes a DTI ratio sustainable.

The regulatory anchor. The 43% QM ceiling defines what mortgage originators can underwrite without legal liability. It became the de facto industry standard precisely because it is a regulatory threshold, not because research established it as the optimal household financial health limit. Mortgage capacity mechanism.

The rate-regime amplifier. DTI is a flow ratio: it captures monthly debt service, not debt stock. When mortgage rates moved from approximately 3% in 2021 to over 7% in 2023, the same purchase price translated into a 40-50% higher monthly payment. The QM Patch — which exempted GSE-eligible loans from the 43% cap until 2021 — masked the constraint during the low-rate era; the post-2022 regime made it binding again.

The income volatility blind spot. A 36% DTI can be perfectly sustainable for a tenured employee with stable income and dangerous for a freelancer or commission-based earner. The ratio assumes a stable denominator, which is increasingly contested in the gig-economy era.

Synthesis by regime: in the low-rate era 2010-2021, 43% DTI was a soft constraint and the QM Patch let lenders push beyond it for conforming loans, contributing to housing affordability deterioration; in the rate-hike regime 2022-2023, the same DTI began to bite, with NAR data showing first-time buyer share collapsing to record lows; in the post-pivot regime 2024-2025, with mortgage rates oscillating between 6% and 7%, the DTI constraint is the primary screen filtering buyers from the market — the transition parameter is the level of the 30-year mortgage rate, not the household balance sheet.

The 43% DTI is a regulatory threshold, not a personal finance law — and what makes it bite is the rate regime, not the household. For the broader picture: the breakdown of bond ETF families by regime.

→ Analytical framework: Real estate, credit and rate cycles

What it means for different economic actors

Borrowers face a different DTI environment than five years ago. The same nominal income covers less debt service at current rates, even when the principal amount is unchanged.

Lenders use DTI primarily as a regulatory shield, not as a borrower welfare measure. Approval at 43% DTI does not certify the loan is affordable — it certifies it is documentable.

Macro analysts watch aggregate household debt service ratios because they signal credit cycle stress. The Fed’s Household Debt Service Ratio bottomed near 9.5% during the pandemic and has risen back toward pre-2008 levels.

A common error is treating DTI as a personal finance ideal — “under 36% means safe” — when it was designed as a lender safe-harbor criterion. Income stability, emergency fund coverage, and rate exposure matter equally.

Practical observation

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Frequently asked questions

How does DTI differ from credit utilization ratio?

DTI measures monthly debt payments against monthly income — it is a cash-flow ratio. Credit utilization measures revolving balances against available credit limits — it is a stock ratio used in FICO scoring. A borrower can have a 30% DTI and 90% credit utilization simultaneously: they pay manageable monthly amounts on cards near their limit. The two metrics capture different dimensions of credit health and are used by different decision-makers — DTI by mortgage underwriters, utilization by credit scoring algorithms.

Why does the 43% threshold persist if it is binding?

The 43% Qualified Mortgage threshold persists because it provides legal safe harbor for lenders against ability-to-repay litigation under the 2010 Dodd-Frank Act. Removing it would require either congressional action or a CFPB rulemaking. The 2021 sunset of the QM Patch, which exempted GSE-eligible loans from the 43% cap, was specifically designed to bring all originations under the same DTI screen — a regime change rarely discussed outside underwriting circles but with measurable effects on first-time buyer access.

Is back-end DTI more relevant than front-end DTI?

Most modern underwriting frameworks emphasize back-end DTI (total debt) over front-end DTI (housing only) because consumers in the 2020s carry more diversified debt portfolios — auto loans averaging $43,582, student loans averaging $39,633 per federal borrower, plus revolving credit. The 28%/36% rule originated in an era when housing dominated household debt; today auto and student debt service often exceeds 10% of income on its own, making front-end DTI an incomplete picture.

Last updated — 12 July 2026