UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 14A
Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.     )
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Filed by a Party other than the Registrant ☐
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☐	Preliminary Proxy Statement
☐	Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))
☐	Definitive Proxy Statement
☒	Definitive Additional Materials
☐	Soliciting Material under §240.14a-12
First Midwest Bancorp, Inc.
(Name of Registrant as Specified In Its Charter)
(Name of Person(s) Filing Proxy Statement, if other than the Registrant)
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☐	Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.
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☐	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.
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2 EASY WAYS TO VOTE AVAILABLE 24 HOURS A DAY You do not need to mail in your proxy card if you vote Online or by Phone Vote by Phone (until 11:59 PM ET on May 14, 2019) Follow these easy steps: •Read the accompanying proxy statement and proxy card. •Call 1-800-690-6903 toll-free in the U.S. or Canada. •Enter the information that is printed in the box marked by the arrow → •Follow the simple recorded instructions. XXXX XXXX XXXX XXXX Vote Online (until 11:59 PM ET on May 14, 2019) Follow these easy steps: •Read the accompanying proxy statement and proxy card. •Go to www.proxyvote.com. •Enter the information that is printed in the box marked by the arrow → •Follow the simple on-screen instructions. XXXX XXXX XXXX XXXX 

ENROLL IN ELECTRONIC DELIVERY You can help reduce the environmental impact of producing hard copy proxy materials by signing up for electronic delivery. Visit http://enroll.icsdelivery.com/fmbi and follow the simple instructions to enroll for electronic delivery. If you elect to receive your First Midwest proxy materials by electronic delivery, you may still request paper copies at any time by contacting us at investor.relations@firstmidwest.com. Please note that although there is no charge for this service, there may be costs to you associated with electronic access such as usage charges from your phone and Internet service providers.