HUD guidelines on debt-to-income ratio is 46.9% on for front-end DTI and 56.9% back-end debt-to-income ratio on automated underwriting system approved borrowers. HUD allows manual underwriting on FHA loans for borrowers who get a refer/eligible per automated underwriting system. Or high debt-to-income ratio borrowers with an approve/eligible can be down graded to a manual underwrite by the mortgage underwriter using underwriter discretion. On manual underwriting, the debt-to-income ratio is 31% front-end and 43% back-end with no compensating factor. 37% front-end and 47% back-end debt-to-income ratio with one compensating factor. 40% front-end and 50% back-end with two compensating factors. Mortgage underwriters can allow higher debt-to-income ratio than the above using underwriter discretion. Fannie Mae and Freddie Mac maximum debt-to-income ratio is 50% on conforming loans for borrowers with 700 credit scores and higher. Borrowers with under 700 credit scores, the maximum debt-to-income ratio on conventional loans is 45%. There is no front-end debt-to-income ratio on conventional loans.