Klaviyo : Q4 2023 Supplemental

Klaviyo Financial Results

Q4 2023 / Fiscal 2023

Forward-Looking Statements and Disclaimer

This presentation includes certain "forward-looking statements" within the meaning of the safe harbor provisions of the Private Securities Litigation Reform Act of 1995, as amended. Other than statements of historical facts, all statements contained in this presentation and accompanying oral commentary, including, but not limited to, statements about Klaviyo's outlook for the first quarter of fiscal year 2024 ending March 31, 2024 and the full fiscal year ending December 31, 2024, and Klaviyo's expectations regarding possible or assumed business strategies, potential growth and innovation opportunities, new products, potential market opportunities, and other similar matters, are forward-looking statements. Words such as "aim," "anticipate," "believe," "contemplate," "continue," "could," "estimate," "expect," "future," "going to," "guidance," "intend," "keep," "may," "opportunity," "outlook," "plan," "potential," "predict," "project," "shall," "should," "strategy," "target," "will," "would," or words of similar meaning or similar references to future periods may identify these forward-looking statements, although not all forward-looking statements contain these identifying words.

Forward-looking statements reflect management's beliefs, expectations and assumptions about future events as of the date hereof, which are inherently subject to uncertainties, risks and changes in circumstances that are difficult to predict and many of which are outside of our control. These risks include, among others, the following: our ability to achieve future growth and sustain our growth rate; our ability to successfully execute our business and growth strategy, such as the success of our investment in our key growth initiatives and our ability to recognize effective areas for growth; our ability to successfully integrate with third-party platforms; our relationships with third parties, such as our marketing agency and technology partners; unfavorable conditions in our industry; our ability to attract new customers, including mid-market and enterprise customers, retain revenue from existing customers and increase sales from both new and existing customers; success of our marketing and sales strategies; costs and expenses associated with being a public company; as well as other risks and uncertainties set forth under the caption "Risk Factors" and elsewhere in our Quarterly Report on Form 10-Q for the quarter ended September 30, 2023, as filed with the Securities and Exchange Commission (the "SEC") on November 7, 2023, and the other filings and reports we make with the SEC from time to time, including our Annual Report on Form 10-K for the year ended December 31, 2023 to be filed with the SEC, which may be obtained on our Investor Relations website at https://investors.klaviyo.com and on the SEC website at www.sec.gov. Moreover, we operate in a very competitive and rapidly changing environment, and new risks may emerge from time to time. It is not possible for our management to predict all risks, nor can we assess the impact of all factors on our business or the extent to which any factor(s) may cause actual results or outcomes to differ materially from those contained in any forward-looking statements we may make. In light of the risks, uncertainties, assumptions, and other factors, the future events and trends discussed in this presentation may not occur and actual results could differ materially and adversely from those anticipated or implied in the forward-looking statements. Therefore, you should not rely on any of the forward-looking statements. Any forward-looking statement made by us in this presentation is based only on information currently available to us and speaks only as of the date on which it is made. Other than as required by law, we assume no obligation to update any written or oral forward-looking statements contained in this presentation that may be made from time to time in the event of new information, future developments or otherwise.

This presentation may contain statistical data, estimates and forecasts that are based on independent industry publications or other publicly available information. We have not independently verified the accuracy or completeness of the information contained in these industry publications and other publicly available information, and usage of the information does not mean or imply that we have adopted the information as our own or independently verified its accuracy. Accordingly, we make no representations as to the accuracy or completeness of the information nor do we undertake to update the information after the date of this presentation.

All third-party brand names and logos appearing in this presentation are trademarks or registered trademarks of their respective holders. Any such appearance does not necessarily imply any affiliation with us or our endorsement of the third-party.

Numbers in this presentation are rounded for presentation purposes. Some of the numbers in this presentation may not tie due to rounding.

2024 © Klaviyo

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Statement Regarding Use of Non-GAAP Financial Measures

In addition to financial measures prepared in accordance with generally accepted accounting principles in the United States (GAAP), this presentation and accompanying oral commentary contain non-GAAP financial measures, including non-GAAP gross profit, non-GAAP operating (loss) income, non-GAAP operating expenses, non-GAAP operating margin, non-GAAP net income, non-GAAP net income per share attributable to Klaviyo Series A and Series B common stockholders - basic, non-GAAP net income per share attributable to Klaviyo Series A and Series B common stockholders - diluted, free cash flow, and free cash flow margin. The non-GAAP financial information is presented for supplemental informational purposes only and is not intended to be considered in isolation or as a substitute for, or superior to, financial information prepared and presented in accordance with GAAP. Please see the Appendix for reconciliations of these non-GAAP financial measures to their nearest GAAP equivalents.

Our non-GAAP gross profit, non-GAAP operating (loss) income, non-GAAP operating expenses, and non-GAAP net income exclude significant expenses and income that are required by GAAP to be recorded in our consolidated financial statements, including, but not limited to, (i) amortization of prepaid marketing expenses, (ii) stock-based compensation and related employer payroll taxes, and (iii) restructuring expenses. Our non-GAAP operating margin is calculated as non-GAAP operating (loss) income divided by total revenue. Our non-GAAP net income per share attributable to Klaviyo Series A and Series B common stockholders - basic is calculated as non-GAAP net income divided by weighted average shares outstanding - basic for purposes of calculating Non-GAAP net income per share. Our non-GAAP net income per share attributable to Klaviyo Series A and Series B common stockholders - diluted is calculated as non-GAAP net income divided by weighted average shares outstanding - diluted for purposes of calculating Non-GAAP net income per share. Free cash flow is defined as cash and cash equivalents provided by or used in operating activities less purchases of property and equipment and capitalization of software development costs. Free cash flow margin is a non-GAAP financial measure that is calculated as free cash flow divided by total revenue.

Stock-based compensation expense includes the net effects of capitalization and amortization of stock-based compensation expense related to capitalized software. Stock-based compensation expense has been, and will continue to be for the foreseeable future, a significant recurring expense in our business and an important part of the compensation provided to our employees. Because of varying available valuation methodologies, subjective assumptions, and the variety of equity instruments that can impact a company's non-cash expenses, we believe that providing non-GAAP financial measures that exclude stock-based compensation expense allows for meaningful comparisons between our operating results from period to period. When evaluating the performance of its business and making operating plans, Klaviyo does not consider these items (for example, when considering the impact of equity award grants, the company places a greater emphasis on the amount of overall stockholder dilution than the accounting charges associated with such grants). The amount of employer payroll tax-related items on employee stock transactions is dependent on restricted stock unit settlements, option exercises, related stock price, and other factors that are beyond Klaviyo's control and that do not correlate to the operation of the business. The amount of employer payroll tax-related items on employee stock transactions was immaterial prior to being publicly listed. The expense related to amortization of prepaid marketing expense of warrants issued to Shopify is dependent upon estimates and assumptions; therefore, Klaviyo believes non-GAAP measures that adjust for the amortization of prepaid marketing expense provide investors a consistent basis for comparison across accounting periods. Klaviyo believes that the economic impact of the partnership is best measured in the form of stockholder dilution and as such have provided a reconciliation that shows the full dilutive impact of all outstanding equity instruments. Overall, Klaviyo believes it is useful to exclude these expenses in order to better understand the long-term performance of its core business and to facilitate comparison of its results period-over-period and to those of peer companies. All of these non-GAAP financial measures are important tools for financial and operational decision-making and for evaluating Klaviyo's own operating results over different periods of time.

We believe that all these non-GAAP financial measures provide useful information about our financial performance, enhance the overall understanding of our past performance and future prospects and allow for greater transparency with respect to decision making by our management, who use these measures as important tools for financial and operational decision-making and for evaluating Klaviyo's own operating results over different periods of time.

Investors are cautioned that there are material limitations associated with the use of non-GAAP financial measures versus their nearest GAAP equivalents. Other companies may calculate non-GAAP financial measures differently or may use other measures to evaluate their performance, all of which could reduce the usefulness of our non-GAAP financial measures as tools for comparison. Further, stock-based compensation expense has been, and will continue to be for the foreseeable future, a significant recurring expense in Klaviyo's business and an important part of the compensation provided to attract and retain its employees to create long-term incentive alignment with stockholders.

2024 © Klaviyo

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Klaviyo powers smarter digital relationships

ActivateConnectGuideGrow

data in real-time to	with customers	marketing with	audience,
better target,	through a	built-in AI,	customer lifetime
personalize, and	seamless email,	automations,	value, and total
measure all	SMS, mobile push,	predictive	revenue
interactions	and reviews	analytics, and
	experience	benchmarks

2024 © Klaviyo

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Klaviyo at a glance1

$698M	117%	31%	16%
Revenue	Dollar-Based Net Revenue	EMEA and APAC	Free Cash Flow Margin3
	Retention Rate2,4	Revenue

48%	143,000+	1,958	11%
Revenue Growth	Total Customers2,4	Customers Generating Over	Non-GAAP
		$50K ARR2,4	Operating Margin3
		80% YoY Growth

• All metrics for fiscal year 2023 ended December 31, 2023, unless otherwise noted.

2	See Appendix for definitions of Dollar-Based Net Revenue Retention Rate, Customers, and Customers Generating Over $50,000 of ARR.	2024 © Klaviyo	5
3	See Appendix for Non-GAAP reconciliation.
4	As of December 31, 2023.

Large and growing customer base1

143,000+

Customers

1,958

Customers > $50K ARR

1 All metrics as of December 31, 2023. See Appendix for definitions of Customers and Customers Generating Over $50,000 of ARR.

2024 © Klaviyo

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We help customers drive revenue

Jones Road, a cosmetics company run by Bobbi Brown, used Klaviyo to help drive a record setting BFCM in 2023. They increased their KAV this BFCM by over 150% year over year.

Strategy

• Used advertisements and social posts to drive demand to Klaviyo forms
• Added limited time product drop details to existing evergreen flows for potential upsell
• Created segments to drive personalized messaging based on different personas

150%+

YoY growth in KAV this BFCM 2023

Use cases:

• Personalized segmentation
• Automated flows
• SIgn up forms
• Pre-builtintegrations

2024 © Klaviyo

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Businesses need to deliver highly personalized experiences to drive revenue growth

01 Initial connection	02 Revenue-driving engagement	03 Real-time engagement	04 Ongoing engagement
Collect first-party data to	Connect with consumers-not	Predictive analytics advise	Predictive analytics create
connect with interested	just to engage-to drive revenue	SMS as the best channel to	personalized emails for ongoing
consumers directly		maximize rapid engagement	promotions, driving ROI and
			attractive LTV

Website	SMS
First-party data
Returning
intake,
customer browse
email + SMS
abandonment
	flow

Email	Email
VIP customer,
Abandoned	post-purchase
cart flow	replenishment
	flow

05 Personalization across channels

Integrated approach results in consistent, personalized experience across channels, including multi-channelon-ramp to customer-owned properties

2024 © Klaviyo

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Delivering impactful consumer experiences is challenging

X Wrong product	X Lack of context	X Fractured experience	X Counterproductive
Messages are impersonal and	Without real-time event data,	Disjointed consumer experience	Lack of context results in
disconnected from consumer	inappropriate messages are sent	across channels and other	suboptimal experiences
interests and preferences		customer-owned properties

After purchasing cat food and kitty litter,	After purchasing a cat tower, consumer	After already subscribing, consumer receives	Consumer has submitted a refund request for
consumer receives an email featuring	receives an abandoned cart email with a	prompt to provide personal information and	a product but is served a request for a review
products for dogs	coupon code	sign up for SMS messaging	email
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Other solutions do not have the full stack to unlock all the capabilities required by creators

		Cloud data warehouses and
Single channel solutions	Marketing solution providers	operational databases

2024 © Klaviyo

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