<PAGE>   1




























                                   EXHIBIT 11

                    COMPUTATION OF EARNINGS PER COMMON SHARE














<PAGE>   2


                                                                     EXHIBIT 11
                                                                     PAGE 1 OF 2



                  UNION PLANTERS CORPORATION AND SUBSIDIARIES
                COMPUTATION OF PRIMARY EARNINGS PER COMMON SHARE




<TABLE>
<CAPTION>
                                                                THREE MONTHS ENDED                NINE MONTHS ENDED
                                                                    SEPTEMBER 30,                     SEPTEMBER 30,
                                                            ---------------------------       -----------------------------      
                                                               1996             1995             1996               1995
                                                            ----------       ----------       ----------         ----------      
                                                                   (DOLLARS IN THOUSANDS, EXCEPT PER SHARE DATA)
<S>                                                         <C>              <C>              <C>                <C>       
PRIMARY EARNINGS PER COMMON SHARE

Average shares outstanding                                  46,184,518       44,889,624       45,880,224         44,532,665

Assumed exercise of options outstanding                        222,158          409,030          216,771            334,626
                                                            ----------       ----------       ----------         ----------      
Primary average shares outstanding                          46,406,676       45,298,654       46,096,995         44,867,291
                                                            ==========       ==========       ==========         ==========

Net earnings                                                $   34,007       $   38,014       $  113,794         $  110,122
Less: Preferred stock dividends
      Series B                                                       -              (88)             (45)              (264)
      Series D                                                       -                -                -               (165)
      Series E                                                  (1,743)          (1,877)          (5,239)            (4,985)
      Preferred stock of an acquired entity                          -             (345)               -             (1,021)
                                                            ----------       ----------       ----------         ----------
Net earnings applicable to common shares                    $   32,264       $   35,704       $  108,510         $  103,687
                                                            ==========       ==========       ==========         ==========

Primary Earnings Per Common Share                           $      .69       $      .79       $     2.35         $     2.31
</TABLE>







<PAGE>   3


                                                                     EXHIBIT 11
                                                                     PAGE 2 OF 2



                  UNION PLANTERS CORPORATION AND SUBSIDIARIES
             COMPUTATION OF FULLY DILUTED EARNINGS PER COMMON SHARE




<TABLE>
<CAPTION>
                                                              THREE MONTHS ENDED               NINE MONTHS ENDED
                                                                 SEPTEMBER 30,                   SEPTEMBER 30,
                                                         ---------------------------       ---------------------------          
                                                            1996             1995             1996             1995
                                                         ----------       ----------       ----------       ----------          
                                                                  (DOLLARS IN THOUSANDS, EXCEPT PER SHARE DATA)
<S>                                                      <C>              <C>              <C>              <C>  
FULLY DILUTED EARNINGS PER COMMON SHARE

Average shares outstanding                               46,184,518       44,889,624       45,880,224       44,532,665
Assumed exercise of options outstanding                     309,532          429,444          246,366          349,466
Assumed conversion of preferred stock
  outstanding:
     Series B                                                     -          339,768          148,804          339,768
     Series D                                                     -                -                -          168,174
     Series E                                             4,355,961        4,370,524        4,363,825        4,048,555
                                                         ----------       ----------       ----------       ----------          
Fully diluted average shares outstanding                 50,850,011       50,029,360       50,639,219       49,438,628
                                                         ==========       ==========       ==========       ==========
                                                         
Net earnings                                             $   34,007       $   38,014       $  113,794       $  110,122
Less: Preferred stock dividends of
      an acquired entity                                          -             (345)               -           (1,021)
                                                         ----------       ----------       ----------       ----------
Net earnings applicable to common shares                 $   34,007       $   37,669       $  113,794       $  109,101
                                                         ==========       ==========       ==========       ==========
Fully Diluted Earnings Per Common Share                  $      .67       $      .75       $     2.25       $     2.20
</TABLE>