You can’t reduce payments on your first mortgage under present law. Sometimes you can “strip” a second mortgage (remove the lien and treat the debt as unsecured) where the value of the property is less than the amount owed on the first mortgage. In Chapter 13, you have to successfully complete your plan before a second mortgage is permanently “stripped”. This is a changing area of the law, and should be dealt with cautiously.

Of course, even a first mortgage can be reduced by “modification”. This is basically a mutual agreement between you and the mortgage holder to change your note. Modifications during a Chapter 13 are not rare. They do require court approval however, because how much you pay one creditor usually affects how much you should pay other creditors.