What is the difference between a co-borrower and a co-signer?

A co-borrower is on the title and the loan. A co-signer guarantees the loan but is usually not on title.

Co-borrower and co-signer are often used interchangeably but are distinct under most mortgage programs. A co-borrower is jointly responsible for the loan AND is on the property title - they have ownership rights, share in equity, and are equally liable for the debt. Co-borrowers contribute their income to qualifying. A co-signer (sometimes called "non-occupant co-borrower") is jointly liable for the loan but typically does not appear on title - they have no ownership interest. The IRS and many state laws treat title and liability separately. FHA allows non-occupant co-borrowers (a parent helping an adult child) - both incomes qualify, both are on the loan, both are on title. Conventional allows non-occupant co-borrowers but with stricter LTV caps. VA does not permit non-occupant co-borrowers (only veteran spouses). USDA prohibits non-occupant co-borrowers entirely. The legal effect: defaulting on a co-signed loan damages both parties' credit and creates joint legal liability. Co-signers should plan to be on the loan for the long haul - most lenders don't allow easy removal post-close.