1 EXHIBIT 12.1 US XCHANGE L.L.C RATIO OF EARNINGS TO FIXED CHARGES FISCAL YEAR ENDED SIX MONTHS ENDED DECEMBER 31, JUNE 30, 1997 1996 1998 1997 ----------- ---------- ------------- --------- SELECTED HISTORICAL DATA Earnings were calculated as follows: Income (loss) before taxes $(5,828,368) $(137,810) $(14,249,088) $(830,994) Add: Fixed charges 91,043 - 822,277 2,922 Deduct: Capitalized interest - - 10,300 - ----------- --------- ------------ --------- Earnings $(5,737,325) $(137,810) $(13,437,111) $(828,072) ----------- --------- ------------ --------- Fixed charges were calculated as follows: Interest expense 30,452 - 630,196 - Amortization of debt issuance costs - - 13,910 - Portion of rentals attributable to interest 60,591 - 167,871 2,922 Capitalized interest - - 10,300 - ----------- --------- ------------ --------- Fixed charges $ 91,043 - $ 822,277 $ 2,922 ----------- --------- ------------ --------- Ratio of earnings to fixed charges - - - - ----------- --------- ------------ --------- Deficiency $ 5,828,368 $ 137,810 $ 14,259,388 $ 830,994 ----------- --------- ------------ ---------