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, 2014

NATIONAL PENN BANCSHARES, INC.

(Exact name of registrant as specified in its charter)

645 Hamilton Street, Suite 1100

Allentown, PA 18101

(Address of principal executive offices)(Zip Code)

Registrant’s telephone number, including area code: (800) 822-3321

N/A

(Former name or former address, if changed since last report)

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:

x 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))

Section 8 – Other Events

Item 8.01 Other Events

On September 8, 2014 National Penn Bancshares, Inc. issued a press release announcing the commencement of a public offering of its senior notes. This press release is filed in this Report as Exhibit 99.1 and incorporated herein by reference.

In addition, in August 2014, National Penn Bank (“Bank”) received regulatory approval for and completed a $100 million permanent return of capital from the Bank to its holding company, National Penn Bancshares, Inc.

Section 9 – Financial Statements and Exhibits

Item 9.01 Financial Statements and Exhibits

(d) Exhibits

SIGNATURE

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.

Exhibit Index