Ways that having bad credit can affect a person's ability to qualify for a mortgage include having his application rejected outright and having to pay a higher interest rate, notes Ciele Edwards of SFGate. One spouse's bad credit score can potentially negatively offset the other spouse's good credit score.
Mortgage lenders consider a borrower's credit history, when deciding whether to approve him for a mortgage, according to Edwards. Lenders use an applicant's credit history to determine how likely it is that he can successfully pay his mortgage. A credit score that's less than 600 can cause an application to be denied.
In addition to bad credit, old debts the applicant failed to pay in the past can negatively affect his chances of being approved for a loan, notes Edwards. This applies even if the individual consistently pays his current creditors on time. A majority of items on a person's credit report are eliminated after seven years, but tax liens, judgements, bankruptcy and other items can remain long after seven years.
Past credit information and current credit practices both impact a person's credit score, according to Edwards. Having a high balance on a current credit account and shutting down old credit accounts can negatively impact a borrower's overall credit score.