The 28% rule states that you should spend 28% or less of your monthly gross income on your mortgage payment (e.g. principal, interest, taxes and insurance). To determine how much you can afford using this rule, multiply your monthly gross income by 28%. For example, if you make $10,000 every month, multiply $10,000 by 0.28 to get $2,800. Using these figures, your monthly mortgage payment should be no more than $2,800.
