<PAGE>
PROSPECTUS SUPPLEMENT DATED OCTOBER 6, 2000 FILED PURSUANT TO RULE 424(b)(3)
(To Prospectus Dated October 1, 1999) SEC FILE NO. 333-84661
$100,000,000
ITC/\DeltaCom
4 1/2% Convertible Subordinated Notes Due 2006
This prospectus supplement relates to resales by the holders of
ITC/\DeltaCom, Inc.'s 4 1/2% Convertible Subordinated Notes due 2006 and the
shares of ITC/\DeltaCom's common stock, par value $.01 per share, issuable upon
conversion of the notes. This prospectus supplement should be read in
conjunction with the prospectus dated October 1, 1999, which is to be delivered
with this prospectus supplement.
The information appearing under the heading "Selling Holders" in the
prospectus is superseded in part by the information included in the table below.
<TABLE>
<CAPTION>
Principal Principal
Amount of Notes Amount of Common
Beneficially Notes Stock Owned Common
Owned Prior Offered Prior to the Stock Offered
Name to the Offering Hereby Offering(1) Hereby(2)
---- ---------------- -------- ------------ -------------
<S> <C> <C> <C> <C>
Bear Stearns & Co. .............................. $ 1,375,000 $ 1,375,000 51,556 51,556
White River Securities LLC...................... $ 1,375,000 $ 1,375,000 51,556 51,556
Triton Capital Investments, Ltd. ................ $ 5,250,000(4) $ 5,250,000 196,850(4) 196,850
Greyhound Lines.................................. $ 100,000(5) $ 100,000 3,749(5) 3,749
LDG Limited...................................... $ 150,000 $ 150,000 5,624 5,624
TQA Master Fund.................................. $ 1,000,000 $ 1,000,000 37,495 37,495
TQA Master Plus Fund............................. $ 850,000(6) $ 850,000 31,871(6) 31,871
Employee Benefit Convertible Securities
Fund.......................................... $ 225,000(6) $ 225,000 8,436(6) 8,436
Nations Capital Income Fund...................... $ 3,150,000 $ 3,150,000 118,110 118,110
Value Line Convertible Fund, Inc. ............... $ 500,000 $ 500,000 18,747 18,747
Alexandra Global Investment Fund I Ltd. ......... $ 3,000,000(7) $ 3,000,000 112,485(7) 112,485
Conseco Senior Health Insurance Company -
Convertible................................... $ 625,000 $ 625,000 23,434 23,434
Conseco Health Insurance Company-Convertible..... $ 625,000 $ 625,000 23,434 23,434
Conseco Funds Group - Convertible................ $ 1,000,000 $ 1,000,000 37,495 37,495
BNP Arbitrage SNC................................ $ 2,900,000 $ 2,900,000 108,736 108,736
Highbridge International LLC..................... $ 6,255,000(8) $ 6,255,000 234,533(8) 234,533
AFTRA Health Fund................................ $ 250,000 $ 250,000 9,373 9,373
Coditec International Ltd. E (VBL)............... $ 50,000 $ 50,000 1,874 1,874
Faria Fund Ltd. ................................. $ 50,000 $ 50,000 1,874 1,874
Pacific Life Insurance Company................... $ 1,000,000 $ 1,000,000 37,495 37,495
Pitney Bowes Retirement Fund..................... $ 2,000,000 $ 2,000,000 74,990 74,990
Sage Capital..................................... $ 1,300,000(9) $ 1,300,000 48,743(9) 48,743
Morgan Stanley Dean Witter....................... $ 12,527,000(10) $ 12,527,000 469,703(10) 469,703
----------------- ------------- --------------- -----------
Subtotal...................................... $ 45,557,000 $ 45,557,000 1,708,173 1,708,173
Unnamed holders of previously registered
notes(11)..................................... $ 53,548,000 $ 53,548,000 2,007,799 2,007,799
Any other holders of notes or future
transferees from such holders(3).............. $ 895,000 $ 895,000 33,558 33,558
------------- ------------- ----------- -----------
Total......................................... $ 100,000,000 $ 100,000,000 3,749,531 3,749,531
============= ============= =========== ===========
</TABLE>
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(1) Composed of the shares of common stock owned by each selling holder prior
to the offering, including the shares of common stock into which the notes
held by the selling holder are convertible at the initial conversion rate
of $26.67 per share, excluding fractional shares. Fractional shares will
not be issued upon conversion of the notes; rather, cash will be paid in
lieu of fractional shares, if any. The conversion price and the number of
shares of common stock issuable upon conversion of the notes are subject to
adjustment under specified circumstances, which are described in more
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detail in the accompanying prospectus under "Description of
Notes--Conversion of Notes." Accordingly, the number of shares of common
stock issuable upon conversion of the notes may increase or decrease from
time to time.
(2) Assumes conversion into common stock of the full amount of notes held by
the selling holder at the initial conversion rate of $26.67 per share and
the offering of those shares by the selling holder pursuant to this
prospectus supplement and accompanying prospectus. The conversion price and
the number of shares of common stock issuable upon conversion of the notes
are subject to adjustment under specified circumstances which are described
in more detail in the accompanying prospectus under "Description of Notes -
Conversion of Notes." Accordingly, the number of shares of common stock
issuable upon conversion of the notes may increase or decrease from time to
time. Fractional shares will not be issued upon conversion of the notes;
rather, cash will be paid in lieu of fractional shares, if any. The selling
holders may offer and sell pursuant to the prospectus, their notes, the
shares of common stock into which the notes are convertible, or both.
(3) Information concerning other selling holders of notes will be set forth in
additional prospectus supplements from time to time, as required. No holder
may offer notes pursuant to the prospectus until such holder is included as
a selling holder in a supplement to the prospectus in accordance with the
registration rights agreement. Assumes that any other holders of notes or
any future transferee from any such holder does not beneficially own any
common stock other than common stock into which the notes are convertible
at the conversion price of $26.67 per share.
(4) Includes $2,300,000 principal amount of previously registered notes and the
common stock into which those notes are convertible.
(5) Includes $50,000 principal amount of previously registered notes and the
common stock into which those notes are convertible.
(6) Includes $25,000 principal amount of previously registered notes and the
common stock into which those notes are convertible.
(7) Includes $435,000 principal amount of previously registered notes and the
common stock into which those notes are convertible.
(8) Includes $1,000,000 principal amount of previously registered notes and the
common stock into which those notes are convertible.
(9) Includes $1,050,000 principal amount of previously registered notes and the
common stock into which those notes are convertible.
(10) Includes $11,527,000 principal amount of previously registered notes and
the common stock into which those notes are convertible.
(11) Based on information provided to ITC/\DeltaCom by the trustee on October 3,
2000. Excludes $16,412,000 principal amount of previously registered notes
identified in footnotes (4) through (10).
S-2
