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                                                                     EXHIBIT 4.1
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                            TELE-COMMUNICATIONS, INC.


                                       and


                          THE BANK OF NEW YORK, Trustee

                                ----------------


                          SECOND SUPPLEMENTAL INDENTURE
                          Dated as of February 25, 2000


                Supplement to Indenture Dated as of April 1, 1991
                               as supplemented by
             First Supplemental Indenture Dated as of March 9, 1999


                              --------------------


                          10.125% Senior Notes due 2001
                          9.650% Senior Notes due 2003
                        9.800% Senior Debentures due 2012
                       10.125% Senior Debentures due 2022
                          9.250% Senior Notes due 2002
                        9.875% Senior Debentures due 2022
                          8.250% Senior Notes due 2003
                       9.250% Senior Debentures due 2023
                          7.375% Senior Notes due 2000
                         8.750% Senior Debentures 2023


================================================================================

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         THIS SECOND SUPPLEMENTAL INDENTURE (this "Supplemental Indenture") is
made as of February 25, 2000, between TELE-COMMUNICATIONS, INC., a Delaware
corporation ("TCI" or, the "Company"), as successor issuer, and THE BANK OF NEW
YORK, a New York banking corporation (the "Trustee"), as trustee.


                                    RECITALS

         WHEREAS, TCI and the Trustee (as successor trustee to The Connecticut
National Bank ("Connecticut")) are parties to an Indenture, dated as of April 1,
1991, as supplemented by a First Supplemental Indenture, dated as of March 9,
1999 (collectively, the "Original Indenture"), pursuant to which the Company
issued (as successor issuer), and Connecticut authenticated and delivered the
following securities which are, as of the date hereof, currently outstanding
(collectively, the "Securities"):

(a) $100 million aggregate principal amount of the Company's 10.125% Senior
Notes due 2001;

(b) $150 million aggregate principal amount of the Company's 9.650% Senior Notes
due 2003;

(c) $600 million aggregate principal amount of the Company's 9.800% Senior
Debentures due 2012;

(d) $150 million aggregate principal amount of the Company's 10.125% Senior
Debentures due 2022;

(e) $200 million aggregate principal amount of the Company's 9.250% Senior Notes
due 2002;

(f) $100 million aggregate principal amount of the Company's 9.875% Senior
Debentures due 2022;

(g) $550 million aggregate principal amount of the Company's 8.250% Senior Notes
due 2003;

(h) $500 million aggregate principal amount of the Company's 9.250% Senior
Debentures due 2023;

(i) $300 million aggregate principal amount of the Company's 7.375% Senior Notes
due 2000; and

(j) $250 million aggregate principal amount of the Company's 8.750% Senior
Debentures due 2023;

         WHEREAS, the Board of Directors of TCI has determined that it is in the
best interests of TCI to convert its corporate form from a Delaware corporation
to a Delaware limited liability company pursuant to Section 266 of the Delaware
General Corporation Law and Section 18-214 of the Delaware Limited Liability
Company Act (the "Conversion");

         WHEREAS, the Board of Directors of TCI has determined that it is
advisable to amend certain provisions of the Original Indenture which may affect
the Conversion;

         WHEREAS, the Original Indenture provides that the Company and the
Trustee may amend or supplement the Original Indenture or the Securities of any
series without notice to or consent of any Holder of Securities or coupons to
make any change that, in the opinion of the Board of Directors, does not
materially adversely affect the rights of any Securityholder or the Holder of
any coupon;


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         WHEREAS, the Board of Directors of TCI has determined that the
amendments to the Indenture contained in this Supplemental Indenture do not
materially adversely affect the rights of any Securityholder or the Holder of
any coupon; and

         WHEREAS, this Supplemental Indenture has been duly authorized by all
necessary action on the part of TCI.

         NOW, THEREFORE, TCI and the Trustee agree as follows for the equal and
ratable benefit of the Holders:

                                   ARTICLE I

                           DEFINITIONS; INTERPRETATION

SECTION 1.1 Definitions. Capitalized terms that are defined in the preamble or
            the recitals hereto shall have such meanings throughout this
            Supplemental Indenture. Capitalized terms used but not defined in
            this Supplemental Indenture have the meanings assigned thereto in
            the Original Indenture. The meanings assigned to all defined terms
            used in this Supplemental Indenture shall be equally applicable to
            both the singular and plural forms of such defined terms. The term
            "Indenture" as used herein means the Original Indenture, as amended
            and supplemented by this Supplemental Indenture, or as otherwise
            supplemented or amended from time to time by one or more indentures
            supplemental thereto or hereto entered into pursuant to the
            applicable provisions of the Indenture.

SECTION 1.2 Interpretation. References in the Original Indenture (including
            references in the Original Indenture as amended or supplemented
            hereby) to "this Indenture" (and indirect references such as
            "hereunder," "herein" and "hereof") shall be deemed references to
            the Original Indenture as amended and supplemented hereby. All of
            the covenants, agreements and provisions of this Supplemental
            Indenture shall be deemed to be and construed as part of the
            Original Indenture to the same effect as if fully set forth therein
            and shall be fully enforceable in the manner provided in the
            Original Indenture. Except as otherwise provided in this
            Supplemental Indenture, all of the covenants, agreements and
            provisions of the Original Indenture shall remain in full force and
            effect.



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                                   ARTICLE II

                                   AMENDMENTS


SECTION 2.1 Amendments. The following provisions of the Original Indenture are
            hereby amended, modified, supplemented or replaced as follows:

     (a)    The definition of "Board of Directors" contained in Article One,
          Section 1.01 of the Original Indenture is amended to read in its
          entirety as follows: "Board of Directors means the Board of Directors
          of the Company or any authorized committee thereof, or, if the Company
          is not a corporation, the equivalent decision making body thereof or
          authorized committee thereof."

     (b)    The definition of "Officer" contained in Article One, Section
          1.01 of the Original Indenture is amended to add the words "(if any)"
          after the words "Chairman of the Board."

     (c)    The definition of "Subsidiary" contained in Article One, Section
          1.01 of the Original Indenture is amended in its entirety to read as
          follows: "Subsidiary means any corporation, association, partnership
          or other business entity of which a majority of the total voting power
          of the capital stock or other interests (including partnership
          interests) entitled (without regard to the occurrence of a
          contingency) to vote in the election of directors, managers or
          trustees thereof is at the time owned or controlled, directly or
          indirectly, by (i) the Company, (ii) the Company and one or more of
          its Subsidiaries or (iii) one or more Subsidiaries of the Company."

     (d)    Article Four, Section 4.08 is hereby amended to replace the word
          "corporate" appearing in the heading to such section and as the second
          to the last word of such section with the word "legal."

     (e)    Article Five is hereby amended to replace the word "CORPORATION"
          appearing in the heading thereof with the word "ENTITY."

     (f)    Article Five, Section 5.01 is hereby amended to insert the words
          "or limited liability company" after each occurrence of the word
          "corporation."

     (g)    Article Five, Section 5.01 is also hereby amended to insert the
          following words as a new paragraph after the first paragraph thereof:
          "Nothing in this Indenture shall prohibit the Company from effecting a
          conversion pursuant to applicable law of the Company from a
          corporation into a limited liability company or from a limited
          liability company into a corporation, and any such conversion shall
          not be deemed to be a consolidation, merger or transfer subject to the
          requirements of the


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          immediately preceding paragraph, provided, that such conversion by law
          shall not be deemed to affect any obligations or liabilities of the
          Company incurred prior to such conversion (including obligations or
          liabilities with respect to the Securities). Notice of any such
          conversion shall be promptly delivered to the Trustee."

     (h)       Article Ten, Section 10.15 is hereby amended to insert the words
          "or limited liability company" after the word "corporation" in clause
          (2) thereof.

     (i)       Article Ten, Section 10.16 is hereby amended to insert the words
          "or limited liability company" after each occurrence of the word
          "corporation."

                                  ARTICLE III

                                 MISCELLANEOUS

SECTION 3.1    Conflict with the TIA. If any provision of this Supplemental
            Indenture modifies or excludes any provision of the TIA that is
            required under such Act to be part of and govern the Indenture, the
            latter provision of the TIA shall control. If any provision hereof
            modifies or excludes any provision of the TIA that may be so
            modified or excluded, the latter provision of the TIA shall be
            deemed to apply to this Supplemental Indenture, as so modified or
            excluded, as the case may be.

SECTION 3.2    Date and Time of Effectiveness. This Supplemental Indenture
            shall become a legally effective and binding instrument at and as of
            the date hereof.

SECTION 3.3    Securities Deemed Conformed. As of the date hereof, the
            provisions of each Security then outstanding shall be deemed to be
            conformed, without the necessity for any reissuance or exchange of
            such Security or any other action on the part of the Holders, TCI or
            the Trustee, so as to reflect this Supplemental Indenture.

SECTION 3.4    Successors. All agreements of TCI and the Trustee in this
            Supplemental Indenture and in the Indenture shall bind their
            respective successors.

SECTION 3.5    Benefits of Supplemental Indenture. Nothing in this
            Supplemental Indenture, express or implied, shall give to any
            person, other than the parties hereto and their successors
            hereunder, any Agent, Authenticating Agent and the Holders, any
            benefit or any legal or equitable right, remedy or claim under this
            Supplemental Indenture or the Indenture.


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SECTION 3.6    Separability. In case any provision in this Supplemental
            Indenture, or in the Indenture, shall be invalid, illegal or
            unenforceable, the validity, legality and enforceability of the
            remaining provisions shall not in any way be affected or impaired
            thereby, it being intended that all of the provisions hereof shall
            be enforceable to the full extent permitted by law.

SECTION 3.7    Trustee Responsibility. The Trustee assumes no duties,
            responsibilities or liabilities by reason of this Supplemental
            Indenture other than as set forth in the Original Indenture. The
            Trustee assumes no responsibility for the correctness of the
            statements herein contained, which shall be taken as statements of
            TCI. This Supplemental Indenture is executed and accepted by the
            Trustee subject to all of the terms and conditions of its acceptance
            of the trust under the Original Indenture, as fully as if said terms
            and conditions were herein set forth in full.

SECTION 3.8    Headings. The Article and Section headings of this
            Supplemental Indenture have been inserted for convenience of
            reference only, are not to be considered a part of this Supplemental
            Indenture and shall in no way modify or restrict any of the terms or
            provisions hereof.

SECTION 3.9    Counterparts. This Supplemental Indenture may be executed in
            counterparts, each of which shall for all purposes be deemed to be
            an original, and all such counterparts shall together constitute but
            one and the same instrument.

SECTION 3.10   Notices. The addresses for notices to the Company and the
            Trustee set forth in Section 11.02 of the Original Indenture shall
            be amended, without further action, to read in their entirety as
            follows:

       "If to the Company:

                        Tele-Communications, Inc.
                        9197 South Peoria Street
                        Englewood, Colorado 80112
                        Attention: Treasurer

       If to the Trustee:

                        The Bank of New York
                        101 Barclay Street, Floor 21W
                        New York, New York 10286"


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SECTION 3.11   Governing Law. This Supplemental Indenture shall be governed by
               and construed in accordance with the internal laws of the State
               of New York.




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                  IN WITNESS WHEREOF, the parties hereto have caused this
Supplemental Indenture to be duly executed as of the day and year first above
written.



                                                TELE-COMMUNICATIONS, INC.

                                                By
                                                   -----------------------------
                                                   Name:

                                                   Title:


                                                THE BANK OF NEW YORK, as Trustee

                                                By:
                                                   -----------------------------
                                                   Name:

                                                   Title:


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