Company: MYI
Filing Date: 2025-09-05
Form Type: 424B3
Source: 0001193125-25-196285
Chunk: 1

Company: BLACKROCK MUNIYIELD QUALITY FUND III, INC.
Filing Date: 2025-09-05
Form: 424B3
Chunk 1
---
.

Common Shareholders of MIY: You and the preferred shareholders of MIY are being asked to vote as a single class on a proposal to
approve an Agreement and Plan of Reorganization between MIY and the Acquiring Fund (the “MIY Reorganization Agreement”) and the transactions contemplated therein, including the termination of MIY’s registration under the 1940 Act
and the dissolution of MIY under Maryland law (the “MIY Reorganization”). The Acquiring Fund has a similar investment objective and similar investment strategies, policies and restrictions as MIY, although there are some differences.
Preferred shareholders of MIY are also being asked to vote as a separate class on a proposal to approve the MIY Reorganization Agreement and the MIY Reorganization.

Common Shareholders of MVF: You and the preferred shareholders of MVF are being asked to vote as a single class on a proposal to
approve an Agreement and Plan of Reorganization between MVF and the Acquiring Fund (the “MVF Reorganization Agreement” and collectively with the MVT Reorganization Agreement and the MIY Reorganization Agreement, the “Reorganization
Agreements”) and the transactions contemplated therein, including the termination of MVF’s registration under the 1940 Act and the dissolution of MVF under Maryland law (the “MVF Reorganization”). The Acquiring Fund has a
similar investment objective and similar investment strategies, policies and restrictions as MVF, although there are some differences. Preferred shareholders of MVF are also being asked to vote as a separate class on a proposal to approve the MVF
Reorganization Agreement and the MVF Reorganization.

Common Shareholders of the Acquiring Fund: You and the preferred shareholders
of the Acquiring Fund are being asked to vote as a single class on a proposal to approve the issuance of additional common shares of the Acquiring Fund in connection with the MVT Reorganization, the MIY Reorganization and the MVF Reorganization
(each, a “Reorganization”). Preferred shareholders of the Acquiring Fund are also being asked to vote as a separate class on a proposal to approve each Reorganization Agreement and the transactions contemplated therein.

The enclosed Joint Proxy Statement/Prospectus is only being delivered to the Funds’ common shareholders. The preferred shareholders of each Fund are also being asked to attend the Special Meeting and to vote as a separate class with respect to the proposals described above. Each Fund is delivering to its preferred shareholders a separate proxy statement with respect to the proposals described above. The Board of Directors of each