if a already have a mortgage, will that affect the odds of an approval if I am cosigning on another home loan?

The general answer is that your mortgage will be factored in as part of the debt ratio. So assuming you have "expendable" income and the debt stays below the max you would be OK.....obviously I do not have your info to provide a definitive answer. Bottom line is that it will be factored in.

If you can document that the other Borrower on the mortgage loan has paid the last 12 months payments the mortgage loan will be excluded from your debt ratios.

So long as you have enough income to afford both payments and still be within the acceptable debt to income ratio guidelines, you should be ok.. Keep in mind that in regards to the person you are cosigning for, their income and debt will also be added to yours to come up with a combined debt to income ratio.. Without looking at your complete loan profile, it's near impossible to advise you specifically, but in general, this is done all the time.. I'm a preferred Lender with California and Arizona being my primary markets. If you or someone you know is looking for financing options, feel free to contact me or pass along my information. 480-287-5714 WilliamAcres.com NMLS# 226347 / RPM Mortgage NMLS 1541014 / AZMB0121893

The simple answer is yes but this is not a simple question. Are you co-signing for a family member as a non-occupying co-borrower? Are you co-signing on an investment loan? Is the mortgage you currently have for your primary, second home, or investment property? There are way too many variables here to properly answer that question. You are best to speak with a mortgage professional that can review your current situation and goals and properly advise you on your qualifications.