April 24, 2020

Bryan Rowland
General Counsel
Vertex, Inc.
2301 Renaissance Blvd.
King of Prussia, PA 19406

       Re: Vertex, Inc.
           Draft Registration Statement on Form S-1
           Submitted March 30, 2020
           File No. 377-03104

Dear Mr. Rowland:

       We have reviewed your draft registration statement and have the
following comments. In
some of our comments, we may ask you to provide us with information so we may
better
understand your disclosure.

       Please respond to this letter by providing the requested information and
either submitting
an amended draft registration statement or publicly filing your registration
statement on
EDGAR. If you do not believe our comments apply to your facts and circumstances
or do not
believe an amendment is appropriate, please tell us why in your response.

      After reviewing the information you provide in response to these comments
and your
amended draft registration statement or filed registration statement, we may
have additional
comments.

Draft Registration Statement submitted on March 30, 2020

Summary Consolidated Financial and Operating Information
Non-GAAP Financial Data (unaudited), page 12

1.     Please revise to ensure that your presentations of non-GAAP financial
data throughout
       your filing are not more prominent than the comparable GAAP measures. In
this regard,
       also present the comparable GAAP measures for Adjusted EBITDA margin and
free cash
       flow margin. In addition, revise to include all three major categories
of the statements of
       cash flows with your presentation of free cash flow. Refer to Item
10(e)(1)(i)(A) of
       Regulation S-K and Questions 102.06 and 102.10 of the Compliance and
Disclosure
       Interpretations of Non-GAAP Financial Measures.
 Bryan Rowland
FirstName LastNameBryan Rowland
Vertex, Inc.
Comapany NameVertex, Inc.
April 24, 2020
Page 24,
April 2 2020 Page 2
FirstName LastName
2.       Please clarify your explanation of the usefulness of free cash flow
and free cash flow
         margin as liquidity measures or performance measures. In this regard,
you indicate that
         the measures provide useful information in understanding and
evaluating your operating
         results, while your explanation on page 52 indicates that free cash
flow is used in
         evaluating period-to-period comparisons of liquidity.
Capitalization, page 42

3.       We note you refer to "this offering and the use of proceeds" in the
introductory paragraph
         to describe the items reflected in your Capitalization table; however,
in order to provide an
         investor with a clear understanding of the items you have included on
a pro forma as
         adjusted basis, please include a qualitative and quantitative
description for each of the
         specific item(s) for which you are giving effect. In addition,
following the table, you
         indicate that the information presented above includes certain
assumptions. Please clarify
         which information in the table gives effect to those assumptions.
Management's Discussion and Analysis of Financial Condition and Results of
Operations
Overview, page 49

4.       You disclose that you had over 4,000 customers and average annual
recurring revenue per
         customer was over $65,000 as of December 31, 2019. Please revise to
disclose such
         information for each period presented wherever is applicable
throughout the filing.
5.       We note that you derive the majority of your revenue from software
subscriptions and you
         maintain an allowance for subscription cancellations. Please expand
your disclosures to
         describe the cancellation provisions in your contracts. To the extent
that the cancellations
         were significant, please disclose how they have impacted your results
and earnings trends.
6.       We note you are dependent on relationships with third-party publishers
of software
         business applications. Please tell us what consideration you have
given to filing any such
         material licenses, or related agreements, as exhibits to your
registration statement.
7.       You disclose on page 27 that the COVID-19 outbreak has negatively
impacted the global
         economy and may lead to declines in your customers' revenue, spending
and transactions,
         which may adversely affect your revenue. Please discuss the reasonably
known effects of
         the COVID-19 pandemic on your business, financial condition and
operating results. We
         refer you to Item 303 of Regulation S-K. If material, discuss how the
pandemic has
         impacted, or may impact, your growth strategy described here and on
page 5. For
         example, disclose whether you have experienced reduced client spend,
collection issues,
         or the loss of clients since the COVID-19 outbreak began. In this
regard, we note that you
         principally price your solutions based on a customer's revenue base,
and retention and
         expansion of revenue from existing customers is a key factor affecting
your performance.
         For additional guidance, refer to the Division of Corporation Finance
Disclosure Guidance
         Topic No. 9 issued March 25, 2020.
 Bryan Rowland
FirstName LastNameBryan Rowland
Vertex, Inc.
Comapany NameVertex, Inc.
April 24, 2020
April 3 2020 Page 3
Page 24,
FirstName LastName
Components of Our Results of Operations, page 53

8.       Please revise to disclose the reasonably likely material future
effects of the change in
         accounting policy for your stock appreciation rights after becoming a
public business
         entity. Refer to Question 4 of SAB Topic 14.B.
Internal Control Over Financial Reporting, page 64

9.       Please clarify how the errors resulting from the material weaknesses
relating to revenue
         recognition and capitalized software development costs were addressed
in your financial
         statements.
Business, page 72

10.      You discuss in MD&A that your customers are shifting to your cloud
solutions and that
         you expect this trend to continue. Please consider discussing your
technology
         infrastructure for your cloud solutions in the Business section.
Management, page 86

11.      Please revise your executives' biographies to clearly identify the
time periods associated
         with their business experience over the past five years. Refer to Item
401(e) of Regulation
         S-K for guidance.
Consolidated Statements of Cash Flows, page F-6

12.      Please revise to include column headers for each period.
Notes to Audited Consolidated Financial Statements
Note 1. Summary of significant accounting policies
Earnings Per Share, page F-18

13.      Please accurately report the amount of net loss attributable to Class
B stockholders for
         2018 in your illustration of the calculation of diluted net loss per
common share.
Unaudited Pro Forma Earnings Per Share, page F-19

14.      We note that pro forma basic and diluted income per share will give
effect to the number
         of shares of common stock to be issued in the initial public offering
described in the
         registration statement. It is only appropriate to give effect to the
number of shares whose
         proceeds will be used to pay dividends or fund distributions to
shareholders in excess of
         earnings in pro forma per share data. Refer to SAB Topic 1.B.3. Please
revise.
 Bryan Rowland
Vertex, Inc.
April 24, 2020
Page 4
Recently Issued Accounting Pronouncements, page F-20

15.   We note that you intend to adopt ASU 2017-04 prospectively effective in
2020 with
      regard to future business combinations. Please confirm that you will
apply this guidance
      consistently for goodwill impairment tests performed after adoption.
Revise your
      disclosure accordingly.
Note 3. Capitalized software, page F-24

16.   Based on your disclosures, it appears that you do not begin to amortize
capitalized
      software until it is placed in service; however, amortization should
begin when the
      product is available for general release to customers. Refer to ASC
985-20-35-3.
      Similarly, we note from your disclosure on page F-23 that internal-use
software is not
      depreciated until it is placed in service; however, amortization of
internal-use software
      should begin when the software is ready for its intended use. Refer to
ASC 350-40-35-6.
      Please revise accordingly.
Note 7. Employee benefit and deferred compensation plans
SAR Plan, page F-29

17.   Please expand the note to provide the applicable disclosures related to
your stock
      appreciation rights arrangements as required by ASC 718-10-50-2(c)(2) and
(d).
General

18.   Please supplementally provide us with copies of all written
communications, as defined in
      Rule 405 under the Securities Act, that you, or anyone authorized to do
so on your behalf,
      present to potential investors in reliance on Section 5(d) of the
Securities Act, whether or
      not they retain copies of the communications.
       You may contact Becky Chow, Staff Accountant, at (202) 551-6524 or
Melissa Walsh,
Staff Accountant, at (202) 551-3224 if you have questions regarding comments on
the financial
statements and related matters. Please contact Michael C. Foland,
Attorney-Advisor, at (202)
551-6711 or Kathleen Krebs, Special Counsel, at (202) 551-3350 with any other
questions.



                                                            Sincerely,
FirstName LastNameBryan Rowland
                                                            Division of
Corporation Finance
Comapany NameVertex, Inc.
                                                            Office of
Technology
April 24, 2020 Page 4
cc:       Joel Trotter
FirstName LastName