Company: RFMZ
Filing Date: 2025-05-21
Form Type: 424B5
Source: 0001398344-25-009954
Chunk: 5

Company: RiverNorth Flexible Municipal Income Fund II, Inc.
Filing Date: 2025-05-21
Form: 424B5
Chunk 5
---
 the accompanying Prospectus or the SAI, you should rely on this Prospectus Supplement.
You may request a free copy of the SAI, request a free copy of the Fund’s annual and semi-annual reports, request other information
or make shareholder inquiries, by calling (844) 569-4750, by writing to the Fund at 360 S. Rosemary Ave, Suite 1420, West Palm Beach,
FL 33401, or by visiting the Fund’s and the Adviser’s website at rivernorth.com (information included on the website does
not form a part of this Prospectus Supplement or accompanying Prospectus), or from the SEC’s website (sec.gov).

The Fund’s securities do
not represent a deposit or obligation of, and are not guaranteed or endorsed by, any bank or other insured depository institution and
are not federally insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board or any other government agency.

| iv |

<div align='center'>TABLE OF CONTENTS

Prospectus Supplement</div>

|                                        | Page |
| Prospectus Supplement Summary          | S-1  |
| Dividends                              | S-2  |
| Capitalization                         | S-3  |
| Summary Of Fund Expenses               | S-4  |
| Market And Net Asset Value Information | S-7  |
| Use Of Proceeds                        | S-8  |
| Plan Of Distribution                   | S-9  |
| Legal Matters                          | S-10 |
| Incorporation by Reference             | S-10 |
| Additional Information                 | S-11 |

<div align='center'>Prospectus</div>

| PROSPECTUS SUMMARY                             |  1 |
| SUMMARY OF FUND EXPENSES                       | 14 |
| FINANCIAL HIGHLIGHTS                           | 15 |
| SENIOR SECURITIES                              | 15 |
| MARKET AND NET ASSET VALUE INFORMATION         | 16 |
| THE FUND                                       | 17 |
| THE OFFERING                                   | 17 |
| USE OF PROCEEDS                                | 18 |
| INVESTMENT OBJECTIVES, STRATEGIES AND POLICIES | 18 |
| INVESTMENT PHILOSOPHY AND PROCESS              | 18 |
| USE OF LEVERAGE                                | 20 |
| RISKS                                          | 24 |
| MANAGEMENT OF THE FUND                         | 24 |
| NET ASSET VALUE                                | 28 |
| DIVIDENDS AND DISTRIBUTIONS