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                              June 4, 2024

       Cory Sindelar
       Chief Financial Officer
       Calix, Inc.
       2777 Orchard Parkway
       San Jose, California 95134

                                                        Re: Calix, Inc.
                                                            Form 10-K for the
Fiscal Year Ended December 31, 2023
                                                            Form 8-K filed
April 22, 2024
                                                            File No. 001-34674

       Dear Cory Sindelar:

              We have reviewed your May 13, 2024 response to our comment letter
and have the
       following comments.

              Please respond to this letter within ten business days by
providing the requested
       information or advise us as soon as possible when you will respond. If
you do not believe a
       comment applies to your facts and circumstances, please tell us why in
your response.

              After reviewing your response to this letter, we may have
additional comments. Unless
       we note otherwise, any references to prior comments are to comments in
our May 3, 2024 letter.

       Form 8-K filed April 22, 2024

       Exhibit 99.2, page 15

   1.                                                   From your response to
prior comment 4, we note that the non-GAAP adjustment for
                                                        inventory and component
liability charges related to the accelerated move by your
                                                        customers to your new
platforms. Please tell us more about the business transformation
                                                        noted in your response
and explain how it led to the decision to write off $28.7 million of
                                                        inventory and accrued
liabilities related to excess components in the fourth quarter of
                                                        2023. In addition,
describe the nature of these excess components and explain in greater
                                                        detail how you
determined that the amount written-off was not a normal operating
                                                        expense incurred in the
ordinary course of your business. Refer to Question 100.01 of the
                                                        Division of Corporation
Finance   s Compliance & Disclosure Interpretations on Non-
                                                        GAAP Financial
Measures.
 Cory Sindelar
Calix, Inc.
June 4, 2024
Page 2
2.       In your response to our prior comment 4 you state, "the Company made
the decision to
         write off $28.7 million of inventory." It is not clear to us how you
can decide to impair
         inventory. Please provide us with your inventory impairment analysis.
Also, explain to
         us how you tested inventory for impairment in prior periods.
3.       Your response to prior comment 5 explains that the non-GAAP litigation
settlement
         adjustment was not routine in nature and its magnitude was unexpected
and discrete and
         not expected to recur. Please tell us about the legal matter that gave
rise to the litigation
         settlement and summarize the terms of the settlement. In addition,
further explain your
         determination that the amount recognized for the settlement was not a
normal, recurring,
         cash operating expense.
       Please contact Inessa Kessman at 202-551-3371 or Robert Littlepage at
202-551-3361 if
you have questions regarding comments on the financial statements and related
matters.



FirstName LastNameCory Sindelar                                 Sincerely,
Comapany NameCalix, Inc.
                                                                Division of
Corporation Finance
June 4, 2024 Page 2                                             Office of
Technology
FirstName LastName