Mo. Rev. Stat. § 443.923: Effect of mortgage modification.

1. For a mortgage modification described in subsection 2 of this section:

(1) The mortgage continues to secure the obligation as modified;

(2) The priority of the mortgage is not affected by the modification;

(3) The mortgage retains its priority regardless of whether a record of the mortgage modification is recorded in the public land records; and

(4) The modification is not a novation.

2. Subsection 1 of this section applies to one or more of the following mortgage modifications:

(1) An extension of the maturity date of an obligation;

(2) A decrease in the interest rate of an obligation;

(3) If the change does not result in an increase in the interest rate of an obligation as calculated on the date the modification becomes effective:

(a) A change to a different index that is a recognized index if the previous index to which changes in the interest rate were linked is no longer available;

(b) A change in the differential between the index and the interest rate;

(c) A change from a floating or adjustable rate to a fixed rate; or

(d) A change from a fixed rate to a floating or adjustable rate based on a recognized index;

(4) A capitalization of unpaid interest or other unpaid monetary obligation;

(5) A forgiveness, forbearance, or other reduction of principal, accrued interest, or other monetary obligation;

(6) A modification of a requirement for maintaining an escrow or reserve account for payment of an obligation, including taxes and insurance premiums;

(7) A modification of a requirement for acquiring or maintaining insurance;

(8) A modification of an existing condition to advance funds;

(9) A modification of a financial covenant; and

(10) A modification of the payment amount or schedule resulting from another modification described in this subsection.

3. The effect of a mortgage modification not described in subsection 2 of this section is governed by other law.