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                                                                EXHIBIT 12.1
                       WORLDCOM, INC. AND SUBSIDIARIES
               COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES
                           (In Thousands of Dollars)
    

   
<TABLE>
<CAPTION>
                                                                                                           For the Three Months
                                                                   Year Ended December 31,                    Ended March 31,
                                                    -----------------------------------------------------  --------------------
                                                      1993      1994      1995        1996        1997       1997       1998
                                                    -----------------------------------------------------  --------------------
<S>                                                 <C>       <C>       <C>       <C>          <C>         <C>       <C>
Earnings:
  Pretax income (loss) from continuing operations   $209,920  $(50,697) $428,178  $(2,103,259) $  662,891  $ 78,800  $(162,184)
  Fixed charges, net of capitalized interest          47,316    59,689   272,029      273,733     442,015   101,980    115,522
                                                    --------  --------  --------  -----------  ----------  --------  ---------

  Earnings                                          $257,236  $  8,992  $700,207  $(1,829,526) $1,104,906  $180,780  $ (46,662)
                                                    ========  ========  ========  ===========  ==========  ========  =========

Fixed Charges:
  Interest cost                                     $ 38,657  $ 49,203  $257,803  $   262,562  $  482,635  $103,160  $ 153,273
  Amortization of financing costs                      1,792     2,086     2,811        1,742        --        --         --
  Interest factor of rent expense                      9,967    10,300    16,298       19,004      47,280    11,820     13,274
                                                    --------  --------  --------  -----------  ----------  --------  ---------

  Fixed charges                                     $ 50,416  $ 61,589  $276,912  $   283,308  $  529,915  $114,980  $ 166,547
                                                    ========  ========  ========  ===========  ==========  ========  =========
Deficiency of earnings to combined fixed charges
  and preferred stock dividends                     $   --    $(52,597) $   --    $(2,112,834) $     --    $   --    $(213,209)
                                                    ========  ========  ========  ===========  ==========  ========  =========
Ratio of earnings to combined fixed charges
  and preferred stock dividends                       5.10:1    0.15:1    2.53:1      N/A          2.09:1    1.57:1     N/A
                                                    ========  ========  ========  ===========  ==========  ========  =========
</TABLE>
    

   
See Notes to Computation of Ratio of Earnings to Fixed Charges
    


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                  NOTES TO COMPUTATION OF RATIO OF EARNINGS TO
                                 FIXED CHARGES
    


   
(1)      In the first quarter of 1998, the Company recorded a $429 million
         charge for in-process research and development related to the
         CompuServe Merger and AOL Transaction. The charge was based on a
         valuation analysis of certain technologies acquired in these 
         transactions, including the companies' virtual private data networks,
         application hosting products, security systems, next generation network
         architectures, and certain other identified research and development
         projects purchased in the CompuServe Merger and AOL Transaction. At the
         date of the CompuServe Merger and AOL Transaction, the technological
         feasibility of the acquired technology had not yet been established and
         the technology had no future alternative uses.
    

   
         In addition, the Company recorded a one-time charge of $69.5 million
         for employee severance, alignment charges and direct merger costs
         associated with the BFP Merger.
    

   
(2)      Results for 1996 include a $2.14 billion charge for in-process
         research and development related to the MFS Merger. The charge is based
         upon a valuation analysis of the technologies of MFS' worldwide
         information system, the Internet network expansion system of UUNET, and
         certain other identified research and development projects purchased in
         the MFS Merger. The expense includes $1.6 billion associated with UUNET
         and $0.54 billion related to MFS.
    

   
         Additionally, 1996 results include other after-tax charges of $121
         million for employee severance, employee compensation charges,
         alignment charges, and costs to exit unfavorable telecommunications
         contracts and $344 million after-tax write-down of operating assets
         within the Company's core and non-core business. On a pre-tax basis,
         these charges totaled $600.1 million.
    

   
(3)      In 1995, Metromedia converted its Series I Preferred Stock into Common
         Stock, exercised warrants to acquire Common Stock and immediately sold
         its position of 61,699,096 shares of Common Stock in a public offering.
         In connection with the preferred stock conversion, WorldCom made a
         non-recurring payment of $15.0 million to Metromedia, representing a
         discount to the minimum nominal dividends that would have been payable
         on the Series I Preferred Stock prior to the September 15, 1996
         optional call date of approximately $26.6 million (which amount
         included an annual dividend requirement of $24.5 million plus accrued
         dividends to such call date).
    

   
(4)      As a result of the IDB Merger, the Company initiated plans to
         reorganize and restructure its management and operational organization
         and facilities to eliminate duplicate personnel, physical facilities
         and service capacity, to abandon certain products and marketing
         activities, and to take further advantage of the synergies available to
         the combined entities. Also, during the fourth quarter of 1993, plans
         were approved to reduce IDB's cost structure and to improve
         productivity. Accordingly, in 1994 and 1993, the Company charged to
         operations the estimated costs of such reorganization and restructuring
         activities, including employee severance, physical facility abandonment
         and duplicate service capacity. These costs totaled $43.7 million in
         1994 and $5.9 million in 1993.
    

   
         Also, during 1994, the Company incurred direct merger costs of $15.0
         million related to the IDB Merger. These costs include professional
         fees, proxy solicitation costs, travel and related expenses and certain
         other direct costs attributable to the IDB Merger.
    

   
(5)      In connection with certain debt refinancing, the Company recognized in
         1996 and 1993 extraordinary items of approximately $4.2 million and
         $7.9 million, respectively, net of income taxes, consisting of
         unamortized debt discount, unamortized issuance cost and prepayment
         fees. Additionally, in 1996 the Company recorded an extraordinary item
         of $20.2 million, net of income taxes, related to a write-off deferred
         international costs.