Answer: An estoppel letter is used in a transfer or conveyance of real property prior to the Closing transaction. The document is sent to a bank (or other lender), to an HOA (or Condo Association), to a city/municipality, or a tenant requesting payoff of a mortgage, assessments or taxes due, or rental amounts due on a lease, to incorporate these amounts into the Settlement Statement for the buyer and seller of the real estate. Assessments and payments due must be incorporated into the amounts due at Closing and paid at the time of the Closing. Some amounts may be pro-rated, but all must be included in the Settlement Statement. The estoppel letter is the document that facilitates this process.