To cosign a loan, you generally need a FICO score of at least 670, the floor of the “good” credit range, though many lenders prefer 740 or higher. The score is only the starting point. Lenders also look at your income, your existing debt load, and how long you have held steady work, because the whole purpose of adding you to the loan is to give the lender a stronger backup than the primary borrower can offer alone.
How Score Requirements Vary by Loan Type
Scores from 740 to 799 fall in the “very good” range on the FICO scale, and 800 or above is considered exceptional. Both tiers make a cosigner application meaningfully stronger. Below 670, most lenders will either decline the application or offer worse terms.
Exact thresholds depend on the lender, the loan type, and the primary borrower’s overall profile. A cosigner in the mid-600s might still be accepted on some personal or auto loans. Conventional mortgage lenders tend to be stricter.
FHA Loans Follow Different Rules
Government-backed FHA loans set a minimum credit score of 500 for any borrower, including a non-occupant co-borrower (FHA’s version of a cosigner). A score of at least 580 is required to qualify for the 3.5 percent minimum down payment. When more than one borrower is on an FHA loan, the lender uses the lowest score among them to determine eligibility, so a co-borrower with a weak score can hurt the application instead of helping it.1HUD.gov. FHA Single Family Housing Policy Handbook
Income, Debt, and Employment Also Matter
A high score by itself is rarely enough. Lenders run your debt-to-income ratio, comparing your total monthly debt payments to your gross monthly income. For manually underwritten conventional mortgages, Fannie Mae sets a baseline maximum DTI of 36 percent, with room up to 45 percent for borrowers who bring higher credit scores and cash reserves. Loans routed through Fannie Mae’s automated underwriting can go as high as 50 percent.2Fannie Mae. Debt-to-Income Ratios Auto and personal loan lenders each set their own thresholds. The general expectation is that a cosigner has enough disposable income to cover their own expenses plus the entire payment on the cosigned loan.
Employment history counts too. Lenders typically want at least two years of consistent income, either from one employer or within the same line of work. Self-employed cosigners may be asked for two years of tax returns to verify that the income is stable.
What Cosigning Does to Your Credit
Once you sign, the loan appears on your credit report as your obligation, because legally it is. Every payment the primary borrower makes, on time or late, lands on your credit history as if you had taken the loan out yourself. On-time payments can help build credit for both of you. Missed or late payments damage your score even though the money never passed through your hands.
The application itself triggers a hard credit inquiry, which usually costs a few points. That effect fades within about a year. The bigger and longer-lasting impact comes from the payment history on the loan and from the added balance now tied to your name.
How It Affects Your Own Future Borrowing
When you later apply for a mortgage, car loan, or any other credit, lenders count the full monthly payment on the cosigned loan against your DTI. That extra liability can push you past the threshold for your own financing.
One exception can help. If the primary borrower has been paying reliably, Fannie Mae lets a lender exclude a non-mortgage debt from your DTI as long as the person actually making the payments is not an interested party to your transaction, such as the seller of the home you are buying. The lender needs 12 months of canceled checks or bank statements from the primary borrower showing a clean payment record with no delinquencies.3Fannie Mae. Monthly Debt Obligations USDA loan guidelines apply a similar 12-month rule.4USDA Rural Development. HB-1-3555, Chapter 11 – Ratio Analysis
If any late payment shows up in the most recent 12 months, the full monthly liability stays in your DTI, regardless of whose fault the late payment was.
What Happens if the Borrower Stops Paying
Federal regulations require the lender to give you a written notice before you become obligated as a cosigner. That notice spells out the stakes: if the borrower does not pay, you have to. You may owe the full balance plus late fees and collection costs. The lender can come after you without first trying to collect from the borrower and can use the same methods against you it would use against the borrower, including a lawsuit and wage garnishment.5eCFR. 16 CFR 444.3 – Unfair or Deceptive Cosigner Practices
There is no federal requirement that the lender tell you when the borrower first misses a payment. By the time you find out, the account may already be delinquent on your credit report. Late and missed payments stay on your report for seven years, and because payment history is the largest single factor in your FICO score, the damage can be significant. If the debt is sent to collections, that collection account lands on your report too.
Getting Off the Loan Later Is Hard
Cosigning is easier to enter than to exit. The most reliable way out is refinancing: if the primary borrower can qualify for a new loan on their own, the original cosigned loan is paid off and your obligation ends. For auto loans, this is often the only realistic path. The borrower either refinances without you or pays the loan off in full.6Consumer Financial Protection Bureau. If I Co-Signed for a Private Student Loan, Can I Be Released From the Loan?
Some private student loan lenders offer formal cosigner release programs. These usually require the primary borrower to make a set number of consecutive on-time payments, commonly 12 to 48 months, then demonstrate enough credit and income to carry the loan alone. Release is not automatic. The borrower has to apply for it, and the lender evaluates their creditworthiness at that point. Not every lender offers release, and each sets its own criteria, so check the original loan terms before you count on it.
Simply asking the lender to take you off the loan generally does not work. The cosigner agreement is a binding contract, and the lender has no obligation to change it. Your name stays on the loan until it is paid off, refinanced, or formally released.
A cosigner arrangement carries real financial exposure for years. Confirming that your score clears the lender’s bar is the easy part. Deciding whether you can absorb the loan if the borrower cannot is the part worth spending time on.