Debt-to-Income Ratio: How to Calculate DTI for a Mortgage

Your debt-to-income ratio (DTI) is the share of your gross monthly income that goes to monthly debt payments. To calculate it, add up your monthly debt payments, divide the total by your gross monthly income, and multiply by 100. For example, $2,000 in monthly debts on $6,000 of gross monthly income is a DTI of about 33%, the same example the Consumer Financial Protection Bureau uses.

Mortgage lenders use your debt-to-income ratio to judge whether you can afford a new payment. Conventional loans cap DTI between 36% and 50%, depending on how the loan is underwritten, and government and jumbo programs set their own limits. This guide covers the formula step by step, front-end vs. back-end DTI, what counts as a good ratio, limits by loan type, how self-employed income changes the math, and how to lower your number.

What is Debt-to-Income (DTI) Ratio?

Debt-to-income ratio (DTI) is a personal financial metric used to determine how much of an individual's income is available for debt payments.

When applying for loans and other types of credit, lenders may use an individual's DTI ratio to determine if they are suitable borrowers with enough disposable income to pay off the loan installments in time.

The lender usually sets a maximum allowable DTI before approving a loan application. So, having a low DTI provides more opportunities for getting approved for loans with favorable terms and interest rates.

There are two types of DTI:

• Front-end DTI: The front-end debt-to-income (DTI) ratio, or the housing ratio, measures how much you spend on housing. It is usually calculated by dividing housing expenses (like mortgage payments and insurance) by gross income.

• Back-end DTI: Your back-end DTI includes your front-end DTI plus all other debts you pay monthly, like student loans, personal loans, car loans, and credit cards. So the back-end DTI is usually higher since it takes into account all the debts.

Most mortgage lenders will focus on your back-end DTI for loans that aren't government-sponsored because it gives them a more holistic picture of your financial situation.

How DTI Affects Your Mortgage

Lenders consider your DTI when deciding whether to approve your mortgage application. This is because a DTI ratio says a lot about a person's ability to manage debt.

A low debt-to-income ratio shows that you manage your finances well and stay on top of your debts while a high debt-to-income ratio indicates the opposite.

Lenders must apply some level of rationality before approving anyone for a mortgage, especially when that person has high debts.

If you have a low DTI ratio, for example, 15%, your chances of securing a home loan may be higher, though DTI is only one of several factors lenders review. In most cases, a high DTI, like 50% or more, can make it harder to qualify for a mortgage or may limit the loan amount available to you.

How to Calculate Your Debt-to-Income Ratio?

Use the formula below to find your DTI ratio:

DTI = Monthly Payments ÷ Gross Monthly Income x 100

Let's break it down:

1. Add Up Your Minimum Monthly Payments

Focus on your credit score-reported debts as a monthly expense. Examples include credit card payments, student loans, auto, and personal loans.

Use your minimum monthly payment for these calculations, not your account balance or typical monthly payment. For instance, if your required credit card payment every month is $200, that's your minimum due each month. Include only the minimum of $200, even if you contribute $400 or more.

2. Divide Your Monthly Payment By Your Gross Income

Your gross monthly income includes all your earnings monthly before taxes and other deductions. You can include your salary and other income, such as interest and dividends.

Next, divide your total monthly payment by your gross monthly income once you've determined your gross monthly income.

3. Convert the Result to a Percentage

The result will be a decimal value. Multiply that by 100 to determine your DTI ratio.

Example

Let's assume your gross monthly income is $5,000, and your monthly expenses include a student loan of $400, a car loan of $400, and a personal loan of $200.

Your monthly expense is $400 + $400 + $200 = $1,000

$1,000 ÷ $5,000 X 100 = 20

So, your DTI ratio is 20%.

What Is a Good Debt-to-Income Ratio?

Some lenders describe a DTI ratio of 35% or less as manageable, giving a mortgage application a stronger chance of approval, though every lender weighs the number differently.

A 36%-49% DTI indicates that although you manage your debt adequately, there is room for improvement.

And borrowers with DTIs of 50% or more must focus on reducing their debts before applying for a home loan.

There is no single cutoff. Many lenders are most comfortable at 36% or below, and the maximum they will accept depends on the loan program, how the loan is underwritten, and their own guidelines, as the loan-type breakdown below shows.

A common rule of thumb, the 28/36 rule, suggests keeping the mortgage payment at or below 28% of gross monthly income and total debt payments at or below 36%.

Regardless, it is always a good idea to reduce your debt as much as possible.

Maximum DTI for a Mortgage by Loan Type

Each loan program sets its own ceiling. These are the published benchmarks lenders start from:

• Conventional loans: Fannie Mae caps total DTI at 36% for manually underwritten loans, or up to 45% with strong credit and reserves, and at 50% for loans approved through its Desktop Underwriter system.

• VA loans: VA's underwriting rules use 41% as the benchmark. A higher ratio can still be approved with an underwriter's justification, and that extra review is skipped when residual income beats VA's guideline by at least 20%.

• USDA loans: USDA's eligibility rules set 29% for housing costs and 41% for total debt.

• FHA loans: limits come from HUD's Single Family Housing Policy Handbook and depend on whether the loan is approved through automated underwriting or manually.

• Jumbo and non-QM loans: each lender sets its own cap, and many fall between 43% and 50%.

How to Calculate DTI When You're Self-Employed

The formula doesn't change when you work for yourself, but the income side does. Lenders usually start from the net income on your tax returns, after business expenses, and average it over the last two years. Large write-offs lower that number, which pushes your DTI up.

Example: a business owner has $2,400 in monthly debts, including the new mortgage payment. Their tax return shows $72,000 in net profit, or $6,000 a month, so their DTI is 40%. If a bank statement program qualified them on $8,000 a month of deposits after its expense factor, the same debts would put their DTI at 30%.

If write-offs cut your qualifying income, a bank statement loan may count more of it. Our guide on how to calculate self-employed income walks through the full method.

Quick Tips to Improve Your Debt-to-Income Ratio

Lower Your Interest Rates on Debts

Interest rates can increase your monthly payments. So consider refinancing some of your debts or transferring credit balances to lower their interest rates. Negotiate directly with your creditors to reduce your interest rate.

Raise Your Income

You can lower your DTI by starting a side hustle, picking up more hours at your current job, or freelancing. The only requirement is that you prove that your income is regular and sustainable. Most lenders prefer to see a two-year history of each source of income.

Extend the Duration of Your Loan

Consider extending your loan term. You can reduce your monthly payments by extending the loan's term since you're spreading them out. A loan extension, however, often comes with a higher interest rate as a trade-off.

Frequently Asked Questions

What is considered a good debt-to-income ratio for a mortgage?

Under Fannie Mae's guidelines, a conventional loan can be approved with a DTI of up to 50% through automated underwriting, but a ratio of 36% or less leaves the most room for approval and better terms. FHA, VA, USDA, jumbo, and non-QM programs each set their own limits, covered in the loan-type section above.

What is the difference between front-end and back-end DTI?

Front-end DTI only counts your housing costs against your gross income, while back-end DTI adds in every other monthly debt payment, such as credit cards, auto loans, and student loans, on top of housing.

Does DTI include utilities or groceries?

No. DTI is based on debt obligations that show up on your credit report or require a fixed monthly payment, such as loans and credit cards. Everyday living expenses like groceries, utilities, and insurance premiums that aren't tied to a debt are not included.

Can I get a mortgage with a high DTI?

It's harder, but not automatically disqualifying. Some borrowers with a DTI above 43% may still qualify depending on the loan program, compensating factors like strong credit or reserves, and the specific lender's guidelines.

How does self-employment affect DTI calculations?

Self-employed borrowers typically need to document income differently, often through tax returns averaged over two years, since there's no employer-issued pay stub. This can make the income side of the DTI calculation more involved, but the ratio itself is calculated the same way.

Let Modern Day Lending Help You Get the Financing You Deserve

Your DTI is a crucial factor that lenders consider when deciding to approve your application for a mortgage.

However, other factors, like being a freelancer or entrepreneur, can count against you because you don't have a conventional income stream. That's where Modern Day Lending can help.

With our years of experience, we help entrepreneurs, freelancers, and self-employed individuals explore financing options suited to their situation.

Want to learn more? Schedule a consultation with us to discuss your options today.