SCHEDULE 14A (RULE 14a-101)

Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934

Filed by the Registrant ☒

Filed by Party other than the Registrant ☐

Check the appropriate box:

☐ Preliminary Proxy Statement

☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

☐ Definitive Proxy Statement

☒ Definitive Additional Material

☐ Soliciting Material Pursuant to Rule 14a-12

Golub Capital BDC, Inc.

(Name of Registrant as Specified in its Charter)

(Name of Person(s) Filing Proxy Statement, If Other Than the Registrant) Payment of Filing Fee (Check the appropriate box):

☒ No fee required.

☐ Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.

(1) Title of each class of securities to which transaction applies:

(2) Aggregate number of securities to which transaction applies:

(3) Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule 0-11 (Set forth the amount on which the filing fee is calculated and state how it was determined):

(4) Proposed maximum aggregate value of transaction:

(5) Total fee paid:

☐ Fee paid previously with preliminary materials.

☐ Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the form or schedule and the date of its filing.

(1) Amount previously paid:

(2) Form, schedule or registration statement no.:

(3) Filing party:

(4) Date filed:

 

Your Vote Counts! GOLUB CAPITAL BDC, INC. 2022 Annual Meeting Vote by February 3, 2022 11:59 PM ETGOLUB CAPITAL BDC, INC. 200 PARK AVENUE 25TH FLOOR NEW YORK, NY 10166D63783-P63722You invested in GOLUB CAPITAL BDC, INC. and it’s time to vote! You have the right to vote on proposals being presented at the Annual Meeting. This is an important notice regarding the availability of proxy material for the stockholder meeting to be held on February 4, 2022. Get informed before you vote View the Notice and Proxy Statement and Form 10-K online OR you can receive a free paper or email copy of the material(s) by requesting prior to January 21, 2022. If you would like to request a copy of the material(s) for this and/or future stockholder meetings, you may (1) visit www.ProxyVote.com, (2) call 1-800-579-1639 or (3) send an email to sendmaterial@proxyvote.com. If sending an email, please include your control number (indicated below) in the subject line. Unless requested, you will not otherwise receive a paper or email copy.For complete information and to vote, visit www.ProxyVote.com Control #Smartphone users Point your camera here and vote without entering a control numberVirtually at:Vote Virtually at the Meeting* February 4, 2022 9:30 a.m., Eastern Timewww.virtualshareholdermeeting.com/GBDC2022*Please check the meeting materials for any special requirements for meeting attendance.V1.1

 

Vote at www.ProxyVote.comTHIS IS NOT A VOTABLE BALLOT This is an overview of the proposals being presented at the upcoming stockholder meeting. Please follow the instructions on the reverse side to vote these important matters.Voting Items 1. Election of Directors – To elect three Class III directors of the Company who will each serve for a term expiring in 2025 or until his successor is duly elected and qualified. Nominees: 1a. Lawrence E. Golub 1b. Lofton P. Holder 1c. William M. Webster IV 2. To ratify the selection of Ernst & Young LLP to serve as the Company’s independent registered public accounting firm for the fiscal year ending September 30, 2022. 3. To approve an amendment to the Company’s certificate of incorporation to increase the number of authorized shares of capital stock from 201,000,000 shares to 351,000,000 shares, consisting of 350,000,000 shares of common stock, par value $0.001 per share, and 1,000,000 shares of preferred stock, par value $0.001 per share. NOTE: Such other business as may properly come before the meeting or any adjournment thereof.Board RecommendsFor For For For ForPrefer to receive an email instead? While voting on www.ProxyVote.com, be sure to click “Sign up for E-delivery”.D63784-P63722