Washington Proof of Annuity Acquisition is a document used by the Washington State Department of Financial Institutions (DFI) to prove that an annuitant has acquired an annuity. The DFI requires a Washington Proof of Annuity Acquisition before it can approve an annuity contract for sale or use in Washington State. There are two types of Washington Proof of Annuity Acquisition: 1. Single-Premium Annuity Proof of Acquisition: This document is used to verify that the annuitant has acquired an annuity with a single premium. 2. Flexible-Premium Annuity Proof of Acquisition: This document is used to verify that the annuitant has acquired an annuity with multiple or flexible premiums.