1

Calix Investor PresentationACCESS INNOVATION

July 31, 2015

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Safe HarborAll statements other than statements of historical facts contained in this presentation, including statements regarding our future operations and financial position, business strategy and plans and objectives of management for future operations, are forward-looking statements. In some cases, forward-looking statements can be identified by terminology such as “believe,” “may,” “estimate,” “continue,” “anticipate,” “intend,” “should,” “plan,” “expect,” “predict,” “potential,” or the negative of these terms or other similar expressions.

This presentation includes forward-looking statements regarding future events, including but not limited to, our Non-GAAP second quarter 2015 financial guidance; the growth of internet traffic and the requirements for enhanced telecommunication networks; capital spending on telecommunication and broadband products; our ability to develop products and services to help our customers transform their networks, including our B-, C-, and E-Series, BLM platform, P- and T-Series ONTs and GigaCenters, Compass suite of products, such as Service Verify, Open Link Cable, and Consulting services; the acceleration of the adoption of gigabit services; our growth drivers; the ongoing expansion of our total addressable market; and our future business and financial performance.

We have based these forward-looking statements largely on our current expectations and projections about future events and financial trends that we believe may affect our financial condition, results of operations, business strategy and financial needs. These forward-looking statements are subject to a number of risks, uncertainties and assumptions, including those set forth in our filings with the Securities and Exchange Commission (“SEC”), especially in the "Risk Factors" and "Management's Discussion and Analysis of Financial Condition and Results of Operations" sections of our Annual Report on Form 10-K for fiscal year 2014, and various other SEC filings including our Form 10-Q for the first fiscal quarter of 2015.

You should not rely upon forward-looking statements as predictions of future events. We cannot assure you that the events and circumstances reflected in the forward-looking statements will be achieved or will occur. Although we believe that the expectations reflected in the forward-looking statements are reasonable, we cannot guarantee future results, levels of activity,performance or achievements. Moreover, neither we nor any other person assume responsibility for the accuracy and completeness of the forward-looking statements. Except as required by law, we undertake no obligation to update publicly any forward-looking statements for any reason to conform these statements to actual results or to changes in our expectations. You should read our SEC filings and the documents that we have filed with the SEC as exhibits to those filings, with the understanding that our actual future results, levels of activity, performance and achievements may be materially different from what we expect.

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Agenda

Calix: Access InnovationThe Access market opportunityNew product momentumLatest financial updateAppendix

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Calix: Access Innovation

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2015: Over 300 customers to-date have placed orders for G igaCenters2014: Launched Open Link Cable and GigaCenter solutions2012: Ericsson fiber access products and sales channel ac quired 2011: Occam acquired; expanded into EMEA and Australian m arkets2010: IPO on NYSE; Expansion into Latin American market2008: Expanded into MSO market2007: Introduced first E-Series products2006: OSI acquisition added subscriber edge2005: Expanded into Caribbean market2002: Carl Russo appointed CEO; Expansion into Tier 2 car riers2001: Shipped first product - C71999: Calix founded

Company History

6

IOCs

Customer Base with 1,200+ Service ProvidersBroad North American Customer Base with Growth Inte rnationally

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The Broadband Market Opportunity

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“…the clear global leader in gigabit broadband services deployments.”

BroadbandTrends, February 2015.

9

0

200

400

600

800

1000

1200

Mbp

s G.fast for local loops < 500 m and speeds from 150Mb/s to 1 Gb/s

Gigabit Speeds Provide Powerful Differentiation

DOCSIS 3.0 with 4 channel bonding with

speeds up to >100Mb/s

Distance (ft)

Vectored and Bonded Copper Technologies with speeds from

<50Mb/s to >300Mb/s

Gigabit Fiber

100

500

1000

…

…

10

Source: Telecom & Networking Equipment, The FTTP Renaissance, Implications for Vendors – Jefferies Group LLC May 6, 2015

Accelerating Gigabit Deployment Trend

11

14

31

43

65

76

100

0

20

40

60

80

100

120

Q1 2014 Q2 2014 Q3 2014 Q4 2014 Q1 2015 Q2 2015

Leveraged to Key Growth Markets

*Additional customer deployments from Calix customers have been secured but not yet announced.

Calix-Enabled Residential Gigabit Deployment Announ cements *

12

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

100% Aerial/0% MDU

100% Aerial/20% MDU

50% Aerial/0% MDU

50% Aerial/50% MDU

Non-Electronics/Sub Electronics/Sub

Fiber Deployment Cost Model

Source: Suburban FTTP Network Scenarios, Telecom & Networking Equipment, The FTTP Renaissance, Implications for Vendors – Jefferies Group LLC May 6, 2015

Electronics represent ~15-25% of the total capex co st per unit served in a fiber deployment

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Fiber Benefits Customers and Vendors

Source: RVA LLC: North American FTTH Accelerates, Q4 2014.

Higher customer satisfaction with fiberReliability, picture quality and faster speeds for over 90% of usersFewer customer calls compared to DSL and CableBest value for consumers compared to DSL Copper, or CableService providers’ take rates for FTTH reach 46%

FCC Challenge for 2015: Gigabit deployments in all 50 statesCalix-enabled Gigabit deployments in 40 states todayOver 100 announced customer deployments through early July

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Source: RVA LLC: Average Cost of All Services Reported by Consumers by Broadband Type, Q4 2014.

$142

$110

Fiber Drives Higher ARPU

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Source: RVA LLC: Estimated OpEx Savings Among Those With Active FTTH Customers, Q4 2014.

Estimated Opex Savings

FFTH Reduces Service Provider Costs

35%

23%

42%

0-9% 10-19% 20% or greater

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Source: Google Fiber Kansas City, Bernstein Proprietary Census. Survey conducted by Haynes and Company, May 2014.

Fiber Drives High Consumer Take Rates

83%

62%

81%

72%

27%

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

$0

$20,000

$40,000

$60,000

$80,000

$100,000

$120,000

$140,000

Wornall Homestead Countryside Roanoke Cental Hyde Park Community College

Median HH Income Take Rate

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“We think fiber is better than cable and the execution that we have where we have a lot of momentum. There's a lot of positive vibe in the community about our product and we're executing very well. So, we're offering very competitive offers and all that combined is leading the continued growth.”July 30, 2015

“We are planning on spending an additional $100 million in capital next year on fiber. It is a superior asset; it enables us to remain relevant with our customer base.” Sept. 24, 2014

“In the consumer business, FiOS continues to be the driver of our positive revenue trends, resulting in revenue growth of 4.5%. Mass markets, which includes small business, grew 3.2%. FiOS now represents 79% of consumer revenue. In the second quarter, FiOS consumer revenue grew 9.8%...” July 21, 2015

“ Broadband net adds were positive for the first time in nine quarters. Our continued investments to push fiber deeper into the network and shorten loop lengths have improved our capacity and broadband speed availability and are producing improving results from our broadband franchise.”May 7, 2015

“The [REIT] …positions Windstream to accelerate broadband investments and transition to an IP centric network faster…”July 29, 2014

Economics Favor Fiber Solutions

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Fiber is a Bright Spot in Wireline

Source: Company reports

$29

$31

$34

$37

$40

$42

$45

4Q13 1Q14 2Q14 3Q14 4Q14 1Q15 2Q15

Fioptics Rev ($M)

0%

10%

20%

30%

40%

50%

1Q14 1Q14 2Q14 3Q14 4Q14 1Q15 2Q15

Fioptics availability

$2,9

65

$3,0

41

$3,1

25

$3,2

00

$3,3

08

$3,3

52

$3,4

38

4Q13 1Q14 2Q14 3Q14 4Q14 1Q15 2Q15Fios Rev ($M)

30%

32%

34%

36%

38%

40%

42%

4Q13 1Q14 2Q14 3Q14 4Q14 1Q15 2Q15

Fios Internet Penetration Fios Video Penetration

$683

$702

$709

$712

$727

$738

4Q13 1Q14 2Q14 3Q14 4Q14 1Q15

Strategic Rev ($M)

0

100

200

300

5,900

5,950

6,000

6,050

6,100

6,150

4Q13 1Q14 2Q14 3Q14 4Q14 1Q15

Broadband Subscribers ('000s) - LHS

Prism Subscribers ('000s) - RHS

Latest QuarterWireline revenues -1% y/yFioptics revenues +32% y/y

Latest QuarterWireline revenues -2% y/yFios revenues +10% y/y

Latest QuarterWireline revenues -1% y/yStrategic revenues +5% y/yPrism subscribers +25% y/y

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Operators Focus on Increasing Uptake

Source: Telecom & Networking Equipment, The FTTP Renaissance, Implications for Vendors – Jefferies Group LLC, May 6, 2015

The Importance of Subscriber Penetration Rates on F TTP Economics (5-Year NPV and IRR)

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Solutions Leveraged to Broadband Growth

Fiber-based deployments

Subscriber Edge Equipment

Copper-based deployments

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New Product Momentum

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Access Networks: Datacenter to Subscriber

Source: Telecom & Networking Equipment, The FTTP Renaissance, Implications for Vendors – Jefferies Group LLC, May 6, 2015

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Data Center Outside Plant

Fiber Optimized Pay-as-you-grow architecture

Premises

Service optimized

E3-48 716E854G

E7-2E7-20

E5-48

Calix Solutions from Datacenter to Subscriber Edge

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CAPEX $25KCAPEX $8KOPEX $1KOPEX $32K

Central

Office

Generic

Home

20 Mbps

MDU

1:32 split

BPON ONTs

+ 1 GPON system+ 32 GPON ONTs + 2 CO techs (day)+ 32 techs in field (simultaneously)

GPON ONTs

GPON OLTs

BPON OLTs

Total cash spend = $66K -- or $2,063 per home

BPON to GPON upgrade: The Conventional Way

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CAPEX $4K

OPEX $120

Home

MDU

1:32 split

BPON OLTsGPON OLTs

BPON OLTs

+ 1 GPON line card+ 1 GPON OIM- 1 BPON trade-in + 1 CO tech (2 hrs)+ 0 techs in field (no truck roll)

80 Mbps to 1Gbps

GPON ONTs

Auto-detect

PO ONTs

Central

Office

GPON OLTs

Total cash spend = $4.12K -- or $128 per home

BPON to GPON upgrade: The Calix Way

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Cable operators challenged to offer gigabit speeds over existing HFC plantNext gen DOCSIS 3.1 scheduled for initial deployments late 2015 at the earliestLargest unanswered question is the cost per household threshold that forces the switch to fiber-based systems

Cable Networks: The Conventional Way

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Calix Open Link Cable software translates GPON into DOCSIS for a seamless transition

No change to back office OSS or DOCSIS provisioningNo change to service turn-up procedures

Calix Networks: Calix GPON over DOCSIS Today

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Integrated GigaCenter and Compass Consumer Connect Industry’s First Carrier-Class Wi-Fi Premises SolutionRemote activation of new broadband devices and management of home networksGigacenter now with more than 300 service provider customers since its launch in late 2014

GigaCenter: Strong traction with Service Providers

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Before switching to Calix, one service provider’s average DSLAM life was 2 ½ years:

“I repurchased these assets 3 times before the end of

their depreciable life.”

After 10 years, same Calix C7s that initially delivered ADSL services are delivering advanced VDSL2 and GPON services

Calix Customers Report Higher ROIC

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G.fast brings gigabit experience to brownfield MDUs

G.fast solutions are ideally suited for short loops < 500 m and speeds from 150Mb/s to 1 Gb/sPer U.S. Census data there are over 34 million multi-tenant housing units in the U.S. (per 2013 ACS) with an estimated more than 50% of these units built before 1980Aged residential and commercial units are characterized by difficulties in riser access and restricted building accessG.fast provides high speed when fiber is not availableOn June 2, 2015 Calix announced a trio of new products which will leverage standards-based G.fast technology to bring a gigabit experience to subscribers located in multi-dwelling unit (MDU), multi-tenant unit (MTU), and high-density single family unit (SFU) dwellings

MDU Tower

Riser

Living Units

G.Fast nodeGPON/AE870

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Latest Financial Update

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Q2 2015: Key Developments

Revenues of $99.1M, +1.1% y/ySlightly above the high-end of $94-$98M guidance led by strength in Tier 2/Tier 3 accountsSixth consecutive quarter at or above revenue guidance rangeFirst half revenues +3.5% y/y

Non-GAAP Gross margins increase to 51.0%, +330bps y/yHighest non-GAAP gross margins as a public company

Near-term favorable product and geographic mix as well as long-term shift to software-centric platform offerings

Positive operating profits on margins and operating expense leverageImproved product mix and leverage off higher revenues

Offset operating expense increase of 14% y/y

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New product momentum continues

GigaCenter momentum continuesService provider customer count increased to over 300 at quarter end

Customer orders and deployments remain strong with solid initial feedback

Calix-enabled gigabit residential deployments increase to 100Deployments up 30% q/q and 3x from year ago levels

Service provider customers accelerating deployment plans as end customer demand remains robust

Two next-generation products announced during the quarterG.fast solutions for MDU and high-density single family unit applications

NG-PON2 cards enabling the ability for our E-Series customers to deliver a multi-gigabit experience to their subscribers

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Q2 2015 Financial Results vs. Guidance

($ in millions, except per share amounts) Actual Guidance

Revenues $99.1 $94.0-$98.0

Non-GAAP gross margin 51.0% 48%-49%

Non-GAAP operating expenses $47.3 $48.0-$49.0

Non-GAAP EPS $0.06 ($0.06) – ($0.02)

Cash flow from operations $5.0 Positive

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Q2 2015 Income Statement Highlights

41.0%42.0%43.0%44.0%45.0%46.0%47.0%48.0%49.0%50.0%51.0%52.0%

$0.0

$20.0

$40.0

$60.0

$80.0

$100.0

$120.0

Q2-

13

Q3-

13

Q4-

13

Q1-

14

Q2-

14

Q3-

14

Q4-

14

Q1-

15

Q2-

15

Revenue Gross Margin (%)

30.0%

35.0%

40.0%

45.0%

50.0%

55.0%

$0.0

$10.0

$20.0

$30.0

$40.0

$50.0

$60.0

Q2-

13

Q3-

13

Q4-

13

Q1-

14

Q2-

14

Q3-

14

Q4-

14

Q1-

15

Q2-

15

Operating Expenses Percent of Revenue

Gross margins of 51.0%Well above 48%-49% guidance due to favorable product and regional mixHighest level of non-GAAP gross margins as a public companyLong-term non-GAAP gross margin target remains >50%

Operating expenses decrease as a percentage of revenues

Operating expenses relative to quarterly revenues peaked in Q1-15Continued R&D investment to support next generation productsSales, Marketing and General expenses decline relative to revenues

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1H 2015 Income Statement Highlights

1H 2015 revenues +3.5% y/yStrength in domestic markets with Tier 2/Tier 3 customersTiming and program shifts in International markets gated resultsNew product momentum with key platform products gaining traction with customers

Gross margins increase on mix and platform investments

1H15 gross margins +320bps y/y and +970bps since 1H10Favorable product and geographic mix in 1H15 relative to 1H14Long-term trend reflective of investments in Unified Access architecture platform

$183.8 $190.2

$0.0

$20.0

$40.0

$60.0

$80.0

$100.0

$120.0

$140.0

$160.0

$180.0

$200.0

1H14 1H15

$M

+3.5% y/y

44.9% 45.2% 47.9% 46.9%50.1%

0.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

1H11 1H12 1H13 1H14 1H15

$M

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Improving Consistency Relative to Guidance

Six consecutive quarters of reported revenues in-line or better than guidance

Despite challenging visibility and uneven customer order patternsNew product momentum remains strong with increasing customer acceptance of platform offering

Expanding gross margins drive Non-GAAP EPS at or above guidance for six consecutive quarters

Focused planning process drives strategic investments in platform offeringOn going benefits from shift to software-centric platform and product-specific momentum

$75

$80

$85

$90

$95

$100

$105

$110

$115

Q 1 2 0 1 4 Q 2 2 0 1 4 Q 3 2 0 1 4 Q 4 2 0 1 4 Q 1 2 0 1 5 Q 2 2 0 1 5

RE

VE

NU

ES

IN $

M

($0.15)

($0.10)

($0.05)

$0.00

$0.05

$0.10

$0.15

$0.20

Q 1 2 0 1 4 Q 2 2 0 1 4 Q 3 2 0 1 4 Q 4 2 0 1 4 Q 1 2 0 1 5 Q 2 2 0 1 5

NO

N-G

AA

P E

PS

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Focused on Profitable Growth

1H15 revenues +3.5% y/yIncluding mid-point of guidance for Q3-15 and consensus estimates for Q4-15, 2H15 revenues +5.5% y/yStrong momentum with key new products such as Gigacenter and steady demand from Tier 2/Tier 3 customers

Consistent improvement in non-GAAP gross margins

Continuing benefits from shift to software-centric platform offering as opposed to single-point solutions Calix value proposition validated as key new products drive lower total cost of ownership

$232.9

$287.0

$344.7 $330.2

$382.6 $401.2

$419.4

$0.0

$50.0

$100.0

$150.0

$200.0

$250.0

$300.0

$350.0

$400.0

$450.0

2009 2010 2011 2012 2013 2014 2015E

$MRevenue for 2015 includes Guidancemid-point and Consensus estimate forQ4 2015

35.5%

41.8%43.7% 44.4%

47.3% 46.7%49.8%

0.0%

10.0%

20.0%

30.0%

40.0%

50.0%

60.0%

2009 2010 2011 2012 2013 2014 2015E

2015 gross margins include Q3 2015 Guidance mid-point and consensus Q4 2015 estimate

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Balance Sheet & Cash Flows Highlights

Cash and equivalents of $99.5M$3.4M used to buyback 435K shares of CALX common shares with more than $36.6M left on remaining authorization$1.9M spent on capital expenditures

Operating cycle of 128 daysInventory days decreased q/q to 91 days from 102 days in the prior quarter and 93 days in the year ago quarter due to shipment linearityDSOs flat q/q at 37 days and down slightly from 38 days in the year ago quarter

$69.4M

$80.1M $83.0M

$75.5M$79.3M

$88.1M

$112.0M

$97.8M $99.5M

$0.0M

$20.0M

$40.0M

$60.0M

$80.0M

$100.0M

$120.0M

Q2-

13

Q3-

13

Q4-

13

Q1-

14

Q2-

14

Q3-

14

Q4-

14

Q1-

15

Q2-

15

140 Days

119 Days130 Days

150 Days

131 Days

118 Days111 Days

139 Days128 Days

0 Days

20 Days

40 Days

60 Days

80 Days

100 Days

120 Days

140 Days

160 Days

Q2-

13

Q3-

13

Q4-

13

Q1-

14

Q2-

14

Q3-

14

Q4-

14

Q1-

15

Q2-

15

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Q3 2015 Operating Performance Guidance

Revenues $107-$111M

Gross margin 49-50%

Operating expenses $50-$51M

Non-GAAP EPS $0.05 – $0.09

Cash flow from operations Positive

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Appendix

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Non-GAAP to GAAP Reconciliation

The Company uses certain non-GAAP financial measures in this press release to supplement its consolidated financial statements, which are presented in accordance with GAAP. These non-GAAP measures include non-GAAP net income (loss) and non-GAAP basic and diluted income (loss) per share. These non-GAAP measures are provided to enhance the reader's understanding of the Company's operating performance as they primarily exclude certain non-cash charges for stock-based compensation and amortization of acquisition-related intangible assets, and non-recurring acquisition-related and other expenses, which the Company believes are not indicative of its core operating results. Management believes that the non-GAAP measures used in this presentation provide investors with important perspectives into the Company's ongoing business performance and management uses these non-GAAP measures to evaluate financial results and to establish operational goals. The presentation of these non-GAAP measures is not meant to be a substitute for results presented in accordance with GAAP, but rather should be evaluated in conjunction with those GAAP results. A reconciliation of the non-GAAP results to the most directly comparable GAAP results is provided in this presentation. The non-GAAP financial measures used by the company may be calculated differently from, and therefore may not be comparable to, similarly titled measures used by other companies.

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Non-GAAP to GAAPQ2 2015 Reconciliation

(Unaudited in thousands, except earnings per share data)

Non-GAAPStock-Based

Compensation

Amortization of Intangible

AssetsAcquisition-

Related Costs GAAP

Revenue $ 99,129 $ — $ — $ — $ 99,129

Cost of revenue 48,541 211 2,088 — 50,840

Gross profit 50,588 (211) (2,088) — 48,289

Gross margin 51.0% (0.2 )% (2.1 )% —% 48.7

Operating expenses 47,320 4,130 2,552 52 54,054

Operating income (loss) 3,268 (4,341) (4,640) (52) (5,765)

Interest and other income (expense), net 88 — — — 88

Income (loss) before taxes 3,356 (4,341) (4,640) (52) (5,677)

Provision for income taxes 102 — — — 102

Net income (loss) $ 3,254 $ (4,341) $ (4,640) $ (52) $ (5,779)

Weighted average diluted shares used to

compute non-GAAP net income (loss)

per common share 52,455 52,455 52,455 52,455

Non-GAAP net income (loss) per diluted share $ 0.06 $ (0.08) $ (0.09) $ —

Weighted average basic and diluted shares used to

compute GAAP net loss per common share: 51,950

GAAP net loss per share $ (0.11)

44

Non-GAAP to GAAPQ1 2015 Reconciliation

(Unaudited in thousands, except earnings per share data)

Non-GAAPStock-Based

Compensation

Amortization of Intangible

AssetsAcquisition-

Related Costs GAAP

Revenue $ 91,038 $ — $ — $ — $ 91,038

Cost of revenue 46,285 175 2,088 — 48,548

Gross profit 44,753 (175) (2,088) — 42,490

Gross margin 49.2% (0.2 )% (2.3 )% —% 46.7%

Operating expenses 48,148 3,487 2,552 190 54,377

Operating loss (3,395) (3,662) (4,640) (190) (11,887)

Interest and other income (expense), net 48 — — — 48

Loss before taxes (3,347) (3,662) (4,640) (190) (11,839)

Provision for income taxes 91 — — — 91

Net loss $ (3,438) $ (3,662) $ (4,640) $ (190) $ (11,930)

Weighted average shares used to compute

net loss per common share:

Basic and diluted 51,732 51,732 51,732 51,732 51,732

Net loss per common share:

Basic and diluted $ (0.07) $ (0.07) $ (0.09) $ — $ (0.23)

45

Non-GAAP to GAAPQ2 2014 Reconciliation

(Unaudited in thousands, except earnings per share data)

Non-GAAPStock-Based

Compensation

Amortization of Intangible

Assets GAAP

Revenue $ 98,005 $ — $ — $ 98,005

Cost of revenue 51,221 354 2,088 53,663

Gross profit 46,784 (354) (2,088) 44,342

Gross margin 47.7% — — 45.2%

Operating expenses 41,630 4,050 2,552 48,232

Operating income (loss) 5,154 (4,404) (4,640) (3,890)

Interest and other income (expense), net 42 — — 42

Income (loss) before taxes 5,196 (4,404) (4,640) (3,848)

Provision for income taxes 103 — — 103

Net income (loss) $ 5,093 $ (4,404) $ (4,640) $ (3,951)

Weighted average diluted shares used to compute

non-GAAP net income (loss) per common share 50,961 50,961 50,961

Non-GAAP net income (loss) per diluted share $ 0.10 $ (0.09) $ (0.09)

Weighted average basic and diluted shares used tocompute GAAP net loss per common share 50,573

GAAP net loss per share $ (0.08)

46

Additional Information

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