Both Spouses Are Equally Responsible for a Loan

Whenever a couple takes a loan jointly they are equally for the entire amount of the loan.  There is a common misconception amongst people that the liability for the loan or the monthly payment is divided equally among the two people who have taken a loan jointly.  If your monthly payment on a loan is to $500 and if one of you does not make the payment than the other person is responsible to pay the entire $500 and not just half of that which would be $250.
The account of that is shared jointly by a husband and wife will appear on the credit history of both.  Any positive information as well as negative information shared by that account will be listed on the credit history of both.  It will not matter whether the husband or the wife defaulted on the account.  If there is a late payment it will be reflected on the credit history of both the husband and the wife.
Making all the payments on time will help the credit rating of both the people.