When you apply for a mortgage, a lender considers your debt-to-income ratio, or DTI, as a critical evaluation point.

Your DTI lets lenders know how much money you owe (your debts) compared to how much money you earn (your income), which helps them determine whether you’re financially secure enough to add a mortgage to your current obligations. You could have a good credit score, stable earnings and a great bill-paying record, but if monthly debt repayments already eat up too much of your income, a lender might consider you too much of a risk to take on a mortgage.

That’s why it’s just as important to know your DTI ratio as it is to check your credit score before applying for a mortgage.

Key Takeaways

  • Your debt-to-income (DTI) ratio is a key factor in getting approved for a mortgage
  • The lower the DTI the better. Most lenders see DTI ratios of 36% or less as ideal.
  • It is very hard to get a loan with a DTI ratio exceeding 50%, though exceptions can be made.
  • DTI limits do vary by lender and by type of loan.

What is the debt-to-income (DTI) ratio?

Expressed as a percentage, your debt-to-income ratio is the portion of your gross  (pre-tax) monthly income spent on repaying regularly occurring debts, including mortgage payments, rents, outstanding credit card balances and other loans. It’s a comparison of what’s going out each month vs what’s coming in.

There are two types of ratios that lenders evaluate:

  • Front-end ratio: Also called the housing ratio, this shows what percentage of your income would go toward housing expenses. This includes your monthly mortgage payment, property taxes, homeowners insurance premiums and homeowners association fees, if applicable.
  • Back-end ratio: This shows how much of your income would be needed to cover all monthly debt obligations. This includes the mortgage and other housing expenses, plus credit cards, auto loan, child support, student loans — the predictable, regularly recurring items. Living expenses, such as utilities, are not included, however.

Mortgage lenders might hesitate to work with borrowers with high DTI ratios because there’s a larger risk that they might not be able to repay their loan — given all the other significant demands on their purse. They don’t want you getting in over your head, in other words

How to calculate debt-to-income ratio

You can calculate your DTI ratio before you apply for a mortgage, regardless of which kind of loan you’re looking to get.

Follow these steps to calculate your back-end DTI:

  1. Add up your monthly debt payments: Factor in all of your debt obligations, including rent and house payments, personal loans, auto loans, child support or alimony, student loans and credit card payments. If you’re applying with someone else, combine both of your monthly debts. Don’t include other monthly expenses like food and utilities.
  2. Divide your debts by your monthly gross income: Next, divide your debt payments by your pre-tax monthly income. Again, make sure you’re using the combined debts and income of all mortgage applicants.
  3. Convert the figure into a percentage: The final step is to convert your DTI from a decimal to a percentage, by multiplying it by 100.

Debt-to-income ratio examples

Let’s say your monthly gross income is $6,000. Your monthly rent comes to $1,800. Each month you pay $500 towards your car loan, $150 towards your student loans and $200 toward credit card bills. That adds up to $850.

To calculate your front-end ratio, add up your monthly housing expenses only, divide that by your gross monthly income, then multiply the result by 100. It would come to 30 percent:

To determine the back-end ratio, add up all your monthly debt payments (the rent, the loans and the credit cards) — that would come to $2,650. Then  divide the result by your monthly gross income and convert it into a percentage. It would come to 44 percent:

What is a good debt-to-income ratio?

For conventional loans, most lenders focus on your back-end ratio — the overall tally of your debts vis-à-vis your income. Most conventional loans allow for a DTI of no more than 45 percent, but some lenders will accept ratios as high as 50 percent if the borrower has compensating factors, such as a savings account with a balance equal to six months’ worth of housing expenses.

It probably goes without saying: Lower is better. Lenders generally look for the ideal candidate’s front-end ratio to be no more than 28 percent, and the back-end ratio to be no higher than 36 percent. They then work backward to figure out how much of a mortgage and a mortgage payment you could afford.

Let’s apply that to our examples above. If you’ve got $6,000 in gross monthly income, to have that desired front-end DTI be 28 percent, your maximum monthly mortgage payment would be $1,680 ($6,000 x 0.28 = $1,680). For the 36 percent back-end ratio, your maximum for all debt payments should come to no more than $2,160 per month ($6,000 x 0.36 = $2,160).

In reality, however, depending on your credit score, how much you have in savings and the size of your down payment, lenders may accept higher ratios.

Debt-to-income ratio requirements by loan type

DTI limits vary depending on the lender and the type of loan. While much is at individual lender’s discretion, certain kinds of loans tend to have similar thresholds.

  • Conventional loan: Typically 28% for front-end; for back-end, 36%, up to 45%-50% for otherwise well-qualified borrowers
  • FHA loan: Typically 31% front-end; back-end 43%, up to 57% with exceptions
  • VA loan: no set limits; 41% recommended for back-end
  • USDA loan: Typically 29% for front-end; for back-end, 41%, up to 44% with exceptions

How to lower your debt-to-income ratio

If your debt-to-income ratio is not within the recommended range, you can aim to lower your DTI. Here are some ways:

  • Pay off debt: If possible, the preferred option to lower your DTI is by repaying as much of your debt as you can manage. To make the most impact, prioritize the debt with the highest monthly payment.
  • Refinance existing loans: Seek out options for lowering the interest rate on your debt or attempt to lengthen the duration of the loan.
  • Look into loan forgiveness: These types of programs may help to eliminate some of your debt entirely.
  • Pay off high-interest loans: If you’re unable to refinance your loans, focus on repaying the higher-interest ones first. These carry a heavier weight in your DTI calculation, so paying them off first will improve the ratio.
  • Get a co-signer: If someone who shows sufficient income and good credit — better than yours, preferably — is willing to sign onto the loan with you, it’ll boost your candidacy.  With conventional loans, the co-signer often has to reside in the house. FHA loans don’t carry that requirement.
  • Seek out an additional income: Attack the problem from the opposite end. If you’re able to earn more, it will help improve your DTI ratio.

Bottom line on DTIs and mortgages

Your debt-to-income ratio is an important metric for lenders when considering your application. Not only does it give them insight into your current financial health, it helps them determine if you can handle a mortgage in addition to your other obligations.

The best DTI is the lowest DTI. However, even if yours is on the high side, you may still be able to get a mortgage by refinancing your loans, getting a co-signer or repaying your high-interest loans before lower-interest ones.