Last checked and updated November 2026
Your mortgage debt-to-income ratio (DTI) is the share of your gross monthly income that goes to monthly debt payments. The front-end ratio counts only the new housing payment. The back-end ratio adds every other monthly debt, and it's the one lenders lean on most. The formula: DTI = total monthly debt payments ÷ gross monthly income × 100.
This is the full guide: how to calculate DTI, which debts count, and how each loan program sets its limits. If you only need the caps, see the short answer on max DTI for a mortgage.
Maximum DTI by Loan Type
Limits are written as front-end/back-end where a program sets both. "Manual" means a human underwriter decides without an automated approval.
| Loan type | Standard limit | Highest allowed | Source |
|---|---|---|---|
| Conventional (Fannie Mae) | 36% back-end, manual | 45% manual if the borrower meets the credit score and reserve requirements in the Eligibility Matrix; 50% with Desktop Underwriter (DU) | Selling Guide B3-6-02 |
| Conventional (Freddie Mac) | 36% back-end guideline, manual | 45% manual with documented justification; Loan Product Advisor (LPA) sets the limit on LPA loans | Seller/Servicer Guide 5401.2 |
| FHA | 31/43, manual | 37/47 with one compensating factor, 40/50 with two (credit score 580 or higher); no fixed cap in the Handbook when TOTAL Mortgage Scorecard returns an Accept | HUD Handbook 4000.1, II.A.5 |
| VA | 41% back-end guideline | No hard cap; above 41% needs a supervisor-signed justification unless residual income beats VA's guideline by at least 20% | VA Pamphlet 26-7, chapter 4 |
| USDA | 29/41 | GUS Accept needs no waiver; Refer or manual files can reach 32/44 with a waiver, a 680+ credit score for every applicant and one compensating factor | HB-1-3555, chapter 11 |
| Jumbo | Set by each investor | Varies with loan size, credit score and LTV; check the investor's guide | Investor program guides |
| Non-QM | Set by each lender, often 50% | Some full-documentation programs allow 55% with conditions such as a 680+ credit score, 80% maximum LTV and extra reserves | Lender program guides |
What Is a Debt-to-Income Ratio for a Mortgage?
Lenders track two versions of the ratio:
- Front-end ratio (housing ratio): only your future housing payment, meaning principal, interest, taxes and insurance (PITI), plus mortgage insurance and any HOA dues.
- Back-end ratio (total debt ratio): that housing payment plus every other recurring debt, from credit cards to student loans to car payments.
Most programs judge you mainly on the back-end number. FHA and USDA also set a front-end limit, so on those loans both ratios have to pass.
How to Calculate Debt-to-Income Ratio
Add up every minimum monthly debt payment, divide by your gross monthly income, then multiply by 100.
DTI = (Total Monthly Debt Payments ÷ Gross Monthly Income) × 100
Two details trip people up:
- Use the payment, not the balance. A $12,000 car loan with a $350 monthly bill adds $350.
- Use gross income, meaning pay before taxes, insurance premiums and retirement contributions come out. Take-home pay makes the ratio look healthier than what an underwriter will see.
Worked Example
A first-time buyer earns $8,000 a month before taxes and owes:
- Auto loan: $400
- Credit card minimums: $200
- Projected new mortgage payment (PITI): $2,200
Front-end ratio: $2,200 ÷ $8,000 = 27.5%. Back-end ratio: ($2,200 + $400 + $200) ÷ $8,000 = $2,800 ÷ $8,000 = 35%.
Against the table above, this file fits every program: under FHA's 31/43 and USDA's 29/41, under VA's 41% guideline, and under Fannie Mae's 36% manual limit.
What Is a Good DTI? The 28/36 Rule
A back-end DTI of 36% or lower is a strong position. The classic 28/36 rule says housing should take no more than 28% of gross income and total debt no more than 36%. On $6,000 of gross monthly income, that's a housing payment of up to $1,680 and total debt payments of up to $2,160. Higher ratios are common, but above a program's standard limit (36% to 43% for most manually underwritten loans) you need an automated approval or compensating factors.
What Debts Count Toward Your Mortgage DTI?
Underwriters count obligations that appear on your credit report or carry a required monthly payment. Living costs don't enter the formula.
Counted toward DTI:
- Your projected new mortgage payment (PITI)
- Credit card minimum payments
- Auto loans and leases
- Student loans
- Personal loans
- Court-ordered alimony or child support
- Payments on other financed real estate
Not counted toward DTI:
- Groceries and everyday spending
- Utility bills (electric, water, internet)
- Cell phone plans
- Health, auto, or life insurance premiums
- Subscriptions and memberships
If you're buying a primary residence, your current rent drops out, since the new mortgage replaces it. Keep the apartment while you buy elsewhere, and the rent is counted.
For credit cards, the underwriter uses the minimum payment on your credit report. When the report shows no minimum and there's no statement supporting a lower figure, Fannie Mae has the lender count 5% of the balance, so a $6,000 card balance adds $300 a month. Car leases always count, no matter how few months are left on them.
Debts an Underwriter Can Leave Out
Some debts in your name don't have to be counted if they're documented properly. These are Fannie Mae's rules (Selling Guide B3-6-05 and B3-6-07); other programs and individual lenders can be stricter.
| Debt | When it can be excluded |
|---|---|
| Installment loan close to payoff | 10 or fewer monthly payments remain, unless the payment would still strain your budget. Paying the loan down to 10 payments is allowed. FHA is stricter: the loan must be paid off within 10 months, all such payments together can't exceed 5% of gross monthly income, and paying down the balance to reach 10 months isn't allowed (HUD Handbook 4000.1). |
| Credit card paid in full | The balance is paid off at or before closing. The account can stay open. |
| Debt someone else pays | The other person's last 12 months of canceled checks or bank statements show every payment made on time. It doesn't apply if the payer is an interested party such as the seller or real estate agent. |
| Debt assigned to an ex-spouse | A divorce decree or separation agreement assigns it to them, even if the creditor hasn't released you. |
| Business debt in your personal name | Your business pays it, shown by 12 months of canceled company checks, the account has no late payments, and the payment is reflected in the lender's analysis of the business's cash flow. |
| Loan secured by your financial assets | The loan documents show a 401(k), CD, stocks or similar assets as collateral. If the same account counts toward reserves, its value is reduced by the loan amount. |
Max DTI for a Conventional Loan
The max DTI for a conventional loan is 50% when Fannie Mae's Desktop Underwriter approves it, and 45% when it's manually underwritten. A manual Fannie Mae file starts at 36% and can go to 45% only if the borrower meets the credit score and reserve requirements in the Eligibility Matrix (Selling Guide B3-6-02).
Freddie Mac publishes no fixed cap for Loan Product Advisor loans; LPA weighs the ratio inside its overall risk decision. Manually underwritten Freddie Mac loans use 36% as a guideline and can't exceed 45% (Seller/Servicer Guide 5401.2). To justify a ratio between 36% and 45%, Freddie Mac lists factors such as an energy-efficient home, a likely increase in earnings, a 12-month record of carrying a higher payment with good credit, a down payment of at least 25%, or substantial liquid assets.
Individual lenders can set lower limits (overlays). More on agency rules: conventional mortgage guidelines.
FHA Debt-to-Income Ratio Limits
A manually underwritten FHA loan allows a 31% front-end and 43% back-end ratio with no compensating factors, rising to 37/47 with one factor or 40/50 with two, if your credit score is 580 or higher. When FHA's TOTAL Mortgage Scorecard returns an Accept, the Handbook's manual ratio chart doesn't apply and it sets no fixed cap, so approved ratios above 50% are possible.
| FHA manual tier (HUD Handbook 4000.1, II.A.5) | Max ratios | What's required |
|---|---|---|
| Credit score 500–579 or no score | 31/43 | No stretch allowed |
| Credit score 580+ | 31/43 | Nothing extra |
| Credit score 580+ | 37/47 | One of: verified cash reserves, minimal increase in housing payment, or residual income |
| Credit score 580+ | 40/40 | No discretionary debt |
| Credit score 580+ | 40/50 | Two of: cash reserves, minimal housing payment increase, significant income not counted in effective income, or residual income |
| Energy-efficient home | 33/45 | Home meets FHA's energy-efficient home standard |
FHA has its own debt rules too: the stricter 10-month installment rule in the table above, and counting 5% of collection balances when they total $2,000 or more (see the FAQ below). Full program rules: FHA mortgage guidelines.
USDA DTI Limits
USDA's DTI limits are 29% for the housing payment (PITI) and 41% for total debt (HB-1-3555, section 11.2). Files that get an Accept or Accept Full Documentation from USDA's Guaranteed Underwriting System (GUS) don't need a debt ratio waiver to go above those levels.
For a GUS Refer, Refer with Caution or a manually underwritten file, USDA can approve a waiver up to 32% PITI and 44% total debt (section 11.3) when:
- every applicant's validated credit score is 680 or higher, and
- the lender documents at least one compensating factor: three months of PITI in reserves after closing, two years of continuous employment with the current primary employer (not available to self-employed applicants), a new PITI no more than $100 or 5% above the current verified housing expense, whichever is less, or an energy-efficient home.
USDA also lets installment debts with 10 or fewer payments left be omitted if the payment doesn't exceed 5% of monthly repayment income. More on the program: USDA loans.
VA DTI and Residual Income
VA has no hard DTI cap: 41% is a guideline, and residual income matters more. VA Pamphlet 26-7 (chapter 4) calls the ratio secondary to residual income and says it should not by itself trigger approval or rejection.
Residual income is the money left for family support each month after taxes, the housing payment and other monthly obligations. VA compares it with minimum amounts in regional tables based on family size and loan amount. When the DTI is above 41%, the underwriter's supervisor must sign a statement justifying the approval and listing compensating factors, unless residual income exceeds VA's guideline by at least 20%. VA's examples of compensating factors include excellent credit, minimal consumer debt, long-term employment, significant liquid assets and a sizable down payment. More: VA mortgage guidelines.
Jumbo, Non-QM and Other Situations
- Jumbo loans aren't bought by Fannie Mae or Freddie Mac, so each investor sets its own DTI limit, often tiered by loan size, credit score and loan-to-value.
- Non-QM loans have no agency limit. Programs often stop at 50%, and some allow 55% with tighter loan-to-value, credit score and reserve requirements. DSCR loans for investors skip personal DTI and qualify on the property's rental income.
- Self-employed borrowers usually qualify on income averaged from two years of tax returns, so that net-profit figure is the denominator for the whole ratio.
How underwriters document the factors that justify higher ratios: what compensating factors help the borrower.
Pro tip: Guidelines shift constantly based on market conditions and individual lender overlays. To confirm a specific investor's current DTI threshold instead of digging through PDFs, you can use Zeitro Strata — it cross-checks guidelines from 100+ investors and returns citation-backed answers, so you can verify the exact cap, and the source behind it, before submitting a file.
The Qualified Mortgage Rule and the 43% DTI Standard
You may have read about a "43% rule" for Qualified Mortgages (QM). That hard 43% cap no longer applies.
The Consumer Financial Protection Bureau originally required a DTI at or below 43% for General QM status, which gives lenders legal protection under the ability-to-repay rule. The price-based General QM definition took effect on March 1, 2021, and became the only General QM option for applications received on or after October 1, 2022. For most first-lien loans, a loan qualifies as long as its APR is less than 2.25 percentage points above the Average Prime Offer Rate (smaller loans get higher thresholds), even with a DTI above 43%. Lenders still have to consider and verify DTI or residual income.
FHA, VA and USDA loans have their own QM definitions, so the price-based test doesn't govern them. Your real ceiling depends on the program and lender overlay, not on one universal rule.
How DTI Affects Approval, Rate and Affordability
A ratio above the program's limit means a denial regardless of credit history. Below the limit, every extra dollar of recurring debt cuts the housing payment you can qualify for: a borrower earning $15,000 a month with $4,000 of student loans and car leases has far less room for a mortgage than the paycheck suggests.
How to Lower Your Mortgage Debt-to-Income Ratio
- Pay off existing debt: target small balances and loans with high monthly payments first. Eliminating a $300 car payment removes $300 from the top of the ratio.
- Increase your gross income: a raise or documented additional income raises the denominator.
- Avoid new credit: don't finance a car, buy furniture on credit or open new cards in the months before you apply.
- Make a larger down payment: a smaller loan means a smaller payment, which lowers both ratios.
- Add a co-borrower: a non-occupant co-borrower with strong income and little debt can bring the ratio down, within each program's rules.
- Get nontaxable income grossed up: income that isn't taxed, such as part of your Social Security benefits, some disability payments or child support, can be increased for qualifying. Fannie Mae adds 25% (or the actual tax amount if that's higher), so $2,000 a month counts as $2,500. FHA allows the greater of 15% or your tax rate from the previous year.
Pay cards off rather than down. Because the underwriter counts the minimum payment the card issuer reports, cutting a balance in half helps only once a lower minimum shows up, which usually means waiting for the next statement. Time payoffs early: FHA requires the money for a payoff before closing to come from an acceptable, documented source, and on a conventional loan any new debt found after approval makes the lender recalculate your ratio.
FAQs About Mortgage DTI
Q1. What is the max DTI for an FHA loan?
On a manually underwritten FHA loan, 31% front-end and 43% back-end, or up to 40/50 with two compensating factors and a credit score of 580 or higher. With a TOTAL Mortgage Scorecard Accept, HUD Handbook 4000.1 sets no fixed ratio cap.
Q2. What are the USDA DTI limits?
29% for housing and 41% for total debt. A GUS Accept needs no waiver to go higher; other files can reach 32/44 with a waiver, a 680+ credit score for every applicant and at least one compensating factor (HB-1-3555, chapter 11).
Q3. What is the max DTI for a conventional loan?
50% for loans approved through Fannie Mae's Desktop Underwriter and 45% for manually underwritten Fannie Mae or Freddie Mac loans. Freddie Mac's Loan Product Advisor sets the limit for its own approvals.
Q4. What is the max DTI for a VA loan?
There's no hard cap. VA uses 41% as a guideline; above that, the file needs a supervisor-signed justification unless residual income exceeds VA's guideline by at least 20%.
Q5. Is DTI calculated using gross or net income?
Gross income, meaning your earnings before taxes, insurance and retirement contributions. Using take-home pay gives a number that looks better than what an underwriter will see.
Q6. Does the 43% Qualified Mortgage rule still apply?
Not as a hard cap. The CFPB replaced the fixed 43% DTI requirement with a price-based standard in 2021, so loans can qualify with a higher DTI as long as pricing stays within the allowed range. FHA, VA and USDA loans follow their own rules.
Q7. Is rent included in the debt-to-income ratio for a mortgage?
If you're buying a primary residence, current rent drops out since the new mortgage replaces it. If you keep paying that rent while buying another property, it's counted as a debt.
Q8. Can I get a mortgage with a 50% DTI ratio?
Yes, on several programs. Fannie Mae allows up to 50% through Desktop Underwriter, FHA allows 50% on manually underwritten loans with two compensating factors and sets no fixed cap with a TOTAL Accept, and some Non-QM programs go higher. Manually underwritten conventional loans stop at 45%.
Q9. Does my spouse's debt count toward my DTI?
If your spouse isn't on the loan, their separate debts usually stay out. The exception is community property states such as California, Texas and Arizona: on FHA, VA and USDA loans, a non-borrowing spouse's debts count toward your ratio unless state law excludes them (HUD Handbook 4000.1, VA Pamphlet 26-7 chapter 4, USDA HB-1-3555). VA also lets the lender leave those debts out when the spouse has verified, reliable income. Fannie Mae and Freddie Mac conventional loans don't carry this requirement, although an individual lender can add it as an overlay.
Q10. Does paying off a collection account lower my DTI?
If you're making scheduled payments on a collection, paying it off removes that payment from your ratio. FHA goes further: when your collection balances add up to $2,000 or more, the lender must confirm they're paid, include your payment-plan amount, or count 5% of each balance as a monthly payment (HUD Handbook 4000.1, section II.A.4). So on an FHA loan, clearing collections can lower your DTI even if you aren't paying on them. Fannie Mae doesn't require collections to be paid off on a one-unit primary residence (Selling Guide B3-5.3-09), so there a payoff mostly helps your credit profile.
Q11. Does a higher DTI mean a higher interest rate?
Not directly on a conventional loan. In January 2023, FHFA announced an upfront fee for some Fannie Mae and Freddie Mac loans with a DTI above 40%, then rescinded it on May 10, 2023, before it took effect. Fannie Mae's loan-level price adjustments are built on credit score and loan-to-value grids instead. A high ratio can still cost you indirectly, by limiting you to programs that price higher, such as Non-QM loans.
Conclusion
Your mortgage debt-to-income ratio decides whether a loan program will take your file and how large a payment you can carry. Keeping total obligations at or under 36% puts you in the strongest position; above that, the program you choose and its rules for automated approval and compensating factors decide how far you can go.
Review your debts several months before you plan to apply. Pay down high-balance cards, hold off on new loans, and run your own numbers early so nothing catches you off guard. And if you're a mortgage professional working through a tricky file, Zeitro Strata is worth having open in another tab — it's built to cross-check those constantly shifting maximum guidelines in seconds, with sources you can actually verify.