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                                                                     EXHIBIT 8.1



                                 March 25, 1999


Interlinq Software Corporation
11980 N.E. 24th Street
Bellevue, WA  98005

        RE:    MERGER AND REVERSE STOCK SPLIT

Ladies and Gentlemen:

        We have acted as counsel to Interlinq Software Corporation, a Washington
corporation (the "Company"), in connection with a merger (the "Merger") of
Terlin, Inc. with and into the Company pursuant to that Agreement and Plan of
Merger between Terlin, Inc. and the Company dated as of December 29, 1998 (the
"Merger Statement") and a reverse stock split following the Merger (the "Reverse
Stock Split"). The terms of the Merger and the Reverse Stock Split are described
in the Registration Statement of the Company on Form S-4, as filed with the
Securities and Exchange Commission on January 26, 1999 (together with the
Prospectus contained therein and the amendments thereto, the "Registration
Statement"). All capitalized terms used but not defined herein shall have the
respective meanings given to them in the Registration Statement.

        In connection with this opinion, we have examined the Merger Agreement
and the Registration Statement and such other documents as we have deemed
necessary. We have also examined originals or copies, certified or otherwise
identified to our satisfaction, of such other documents, certificates, and
records as we have deemed necessary or appropriate as a basis for the opinion
set forth herein.

        In rendering our opinion, we have participated in the preparation of the
Registration Statement. Our opinion is conditioned on, among other things, the
initial and continuing accuracy of the facts, information, covenants, and
representations set forth in the documents referred to above and the statements
and representations made by officers of the Company and others. In our
examination, we have assumed the genuineness of all signatures, the legal
capacity of natural persons, the authenticity of all documents submitted to us
as originals, the conformity to original documents of all 


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documents submitted to us as certified or photostatic copies and that the
transactions related to the Merger and Reverse Stock Split will be consummated
in the manner contemplated by the Registration Statement.

        In rendering our opinion, we have considered the provisions of the
Internal Revenue Code of 1986, as amended, Treasury Regulations promulgated
thereunder, judicial decisions, and Internal Revenue Service rulings, all as in
effect on the date hereof and all of which are subject to change, which changes
may be retroactively applied. A change in the authorities upon which our opinion
is based could affect our conclusions.

        Based upon and subject to the foregoing, and subject to the discussion
and limitations set forth in the Registration Statement under the heading
"CERTAIN FEDERAL INCOME TAX CONSEQUENCES OF THE MERGER AND REVERSE STOCK SPLIT,"
we are of the opinion that, although the discussion set forth in the
Registration Statement under the heading "CERTAIN FEDERAL INCOME TAX
CONSEQUENCES OF THE MERGER AND REVERSE STOCK SPLIT" does not purport to discuss
all possible United States federal income tax consequences of the Merger and
Reverse Stock Split and the transactions contemplated thereby, such discussion
constitutes a fair and accurate summary of the material United States federal
income tax consequences (other than consequences that are material to a
shareholder based on such shareholder's particular tax situation) of the Merger
and Reverse Stock Split. As indicated in that discussion, we cannot give an
opinion as to whether the Merger and Reverse Stock Split will be treated as part
of a single transaction or instead treated as separate transactions for federal
income tax purposes because of the lack of authority dealing with this type of
question.

        Except as set forth above, we express no opinion to any party as to the
tax consequences, whether federal, state, local or foreign, of the Merger and
Reverse Stock Split. We hereby consent to the filing of this opinion as an
exhibit to the Registration Statement. In giving such consent, we do not thereby
admit that we are in the category of person whose consent is required under
section 7 of the Securities Act of 1933, as amended. We disclaim any undertaking
to advise you of subsequent changes of the facts as assumed herein or any
subsequent changes in applicable law.


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                                             Very truly yours,

                                             Perkins Coie LLP