Filed
Pursuant to Rule 424(b)(3)
Registration
Statement No. 333-296186
PROSPECTUS
SUPPLEMENT NO. 3
(To
the Prospectus dated June 4, 2026)

Up
to 38,461,538 Shares of Common Stock
This
prospectus supplement supplements the prospectus, dated June 4, 2026 (the “Prospectus”), which forms a part of our registration
statement on Form S-1 (File No. 333-296186). This prospectus supplement is being filed to update and supplement the information in the
Prospectus with certain information contained in the Current Report on Form 8-K filed with the Securities and Exchange Commission on
September 11, 2026, which we have attached to this prospectus supplement.
The
Prospectus and this prospectus supplement relate to the proposed offer and resale or other disposition from time to time by Roth Principal
Investments, LLC (“Roth Principal Investments”) of up to an aggregate of 38,461,538 shares of common stock, par value $0.001
per share (“Common Stock”), of Flux Power Holdings, Inc. that we have elected or may, in our sole discretion, elect to sell
to Roth Principal Investments, from time to time after the date of the Prospectus, pursuant to a Common Stock Purchase Agreement, dated
as of May 15, 2026, we entered into with Roth Principal Investments.
Our
shares of Common Stock are listed on The Nasdaq Capital Market under the symbol “FLUX.” On September 10, 2026, the last reported
sale price of our Common Stock on The Nasdaq Capital Market was $0.5715 per share.
This
prospectus supplement should be read in conjunction with the Prospectus, including any amendments or supplements thereto, which is to
be delivered with this prospectus supplement. This prospectus supplement is qualified by reference to the Prospectus, including any amendments
or supplements thereto, except to the extent that the information in this prospectus supplement updates and supersedes the information
contained therein.
This
prospectus supplement is not complete without, and may not be delivered or utilized except in connection with, the Prospectus, including
any amendments or supplements thereto.
Investing
in our Common Stock involves a high degree of risk. You should review carefully the risks and uncertainties described in the section
entitled “Risk Factors” beginning on page 13 of the Prospectus and under similar headings in any amendments or supplements
to the Prospectus.
Neither
the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed
upon the accuracy or adequacy of this prospectus supplement or the Prospectus. Any representation to the contrary is a criminal offense.
The
date of this prospectus supplement is September 11, 2026.
UNITED
STATES
SECURITIES
AND EXCHANGE COMMISSION
Washington,
D.C. 20549
FORM 8-K
CURRENT
REPORT
Pursuant
to Section 13 OR 15(d) of the Securities Exchange Act of 1934
Date
of Report (Date of earliest event reported): September 8, 2026
Commission
File Number: 001-31543

FLUX
POWER HOLDINGS, INC.
(Exact
name of registrant as specified in its charter)
| Nevada |
|
92-3550089 |
| (State or other jurisdiction
of |
|
(I.R.S. Employer |
| incorporation or organization) |
|
Identification Number) |
| |
|
|
| 2685 S. Melrose Drive,
Vista, California |
|
92081 |
| (Address of principal executive
offices) |
|
(Zip Code) |
877-505-3589
(Registrant’s
telephone number, including area code)
Check
the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under
any of the following provisions (see General Instruction A.2. below):
| ☐ |
Written communications
pursuant to Rule 425 under the Securities Act (17 CFR 230.425) |
| |
|
| ☐ |
Soliciting material pursuant
to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) |
| |
|
| ☐ |
Pre-commencement communications
pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) |
| |
|
| ☐ |
Pre-commencement communications
pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) |
Securities
registered pursuant to Section 12(b) of the Act:
| Title
of each class |
|
Trading
Symbol |
|
Name
of each exchange on which registered |
| Common Stock, $0.001 par
value |
|
FLUX |
|
Nasdaq Capital Market |
Indicate
by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405
of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).
Emerging
growth company ☐
If
an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying
with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐
Item
5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of
Certain Officers.
On
September 8, 2026, Mr. Jeff Mason, Chief Operating Officer of Flux Power Holdings, Inc. (the “Company”), tendered his resignation
to be effective September 25, 2026. In connection with the departure of Mr. Mason, Mr. Mason and the Company agreed to enter into a separation
and release agreement (the “Separation Agreement”), pursuant to which Mr. Mason will receive a payment of $5,000, payable
within ten days of the execution of the Separation Agreement, subject to the non-revocation of a general release of claims in favor of
the Company.
The
foregoing description of the Separation Agreement is a summary and is qualified in its entirety by reference to the full text of the
Separation Agreement that the Company expects to enter into with Mr. Mason, a copy of which is expected to be filed with the Company’s
Quarterly Report on Form 10-Q for the period ending September 30, 2026.
SIGNATURES
Pursuant
to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by
the undersigned hereunto duly authorized.
| |
Flux Power
Holdings, Inc. |
| |
a Nevada corporation |
| |
|
|
| |
By: |
/s/ Kevin
Royal |
| |
|
Kevin Royal |
| |
|
Chief Financial Officer
and Secretary |
Dated:
September 11, 2026