Focused on the mid-market

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Safe Harbor This presentation includes certain forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995, including statements concerning our position to execute on our growth strategy in the mid-market, and our ability to expand our leadership position and market opportunity for our inbound platform. These forward-looking statements include, but are not limited to, plans, objectives, expectations and intentions and other statements contained in this press release that are not historical facts and statements identified by words such as "expects," "anticipates," "intends," "plans," "believes," "seeks," "estimates" or words of similar meaning. These forward-looking statements reflect our current views about our plans, intentions, expectations, strategies and prospects, which are based on the information currently available to us and on assumptions we have made. Although we believe that our plans, intentions, expectations, strategies and prospects as reflected in or suggested by those forward-looking statements are reasonable, we can give no assurance that the plans, intentions, expectations or strategies will be attained or achieved. Furthermore, actual results may differ materially from those described in the forward-looking statements and will be affected by a variety of risks and factors that are beyond our control including, without limitation, our history of losses, our ability to retain existing customers and add new customers, the continued growth of the market for an inbound platform; our ability to differentiate our platform from competing products and technologies; our ability to manage our growth effectively to maintain our high level of service; our ability to maintain and expand relationships with our marketing agency partners; our ability to successfully recruit and retain highly-qualified personnel; the price volatility of our common stock, and other risks set forth under the caption "Risk Factors" in our Quarterly Report on Form 10-Q filed on November 4, 2015 and our other SEC filings. We assume no obligation to update any forward-looking statements contained in this document as a result of new information, future events or otherwise. 2

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An inbound marketing and sales SaaS platform Focused on the mid-market 16,500+ customers Customers as of 9/30/15. 4

Continued Momentum Since IPO GROWTH DRIVERS: Domestic International Upsell Customer REVENUE CUSTOMERS ASRPC 5

The Marketing & Sales Playbook IS BROKEN 6

TRADITIONAL INBOUND VS. Cold Calling email Spam Ads SEO Blogging Social 7

The first four years The last four years The next four years 8

Revenue Growth Third Play Sales Marketing Second Play First Play Time 9

VISITOR LEAD OPPORTUNITY All-In-One Marketing & Sales Growth Platform CUSTOMER 10

Platform > Point Solutions 11

Blogging + SEO Screenshot from HubSpot product, 9/18/14 12

Social Inbox + Inbound Database VISITOR LEAD CUSTOMER Screenshot from HubSpot product, March 2015 13

Website + Inbound Database 14

INBOUND15 Paid Product Launches Website Reporting Ads 15

Total Addressable Market 3M companies X $10,607/year >$31.5 Billion International increases companies & New products grow ASRPC >$31.5B -3.0M is US, CAN, and Europe. 1.6M mid-market businesses with a web presence in the United States and Canada. 1.4M mid-market businesses with a web presence in Europe. -AMI Partners data, 2014. Avg. Subscription Revenue per Customer from Q3 15 16

The Power of Inbound Screenshot from HubSpot product, 10/22/15 17

2,700+ Agency Partners Partners as of 9/30/15. 18

125,000+ Members The Inbound Movement 14,000+ Registered Attendees Trained and certified 17,000+ professionals Available in 9 languages BLOG 2.0+ million Monthly Visits Partners stat as of 9/30/15. All other stats as of October 22, 2015. 2,700+ Partners 19

HubSpot customers see an average 5.7x increase in lead generation after 12 months Month 1 Month 12 Customer Age In Months Source: Internal Analysis of >3,000 customers, 2014 20

Customer Growth 14,746 13,607 10,111 8,159 5,783 15,839 16,854 2006 2007 2008 2009 2010 2011 2012 2013 2014 Q1'15 Q2'15 Q3'15 21

HubSpot Pricing Today Upgrade based on contact database size. Cross sell new products into both marketing and sales customers Upgrade based on features. Pricing as of November 4, 2015 22

Average Subscription Revenue Per Customer $10,000 $9,000 $8,000 $7,000 $6,000 $10,127 $10,607 $9,740 $8,926 $7,752 $6,580 $5,395 $5,000 $4,000 $3,000 $2,000 $1,000 $- Editions Editions + Contacts Editions + Contacts + Add Ons 2011 2012 2013 2014 Q1'15 Q2'15 Q3'15 23

Revenue Growth $115.9M $38.2M 58% Y/Y $42.9M 58% Y/Y $47.7M 57% Y/Y $77.6M $51.6M Q1 15 Q2 15 Q3 15 $6.6M $15.4M $28.6M 2009 2010 2011 2012 2013 2014 24

Key Financial Metrics Key financial metrics 2011 2012 2013 2014 Q1 15 Q2 15 Q3 15 Gross Margin 61% 70% 65% 70% 73% 75% 75% % of revenue R&D 27% 19% 18% 17% 15% 15% 14% S&M 82% 66% 67% 63% 57% 56% 62% G&A 21% 16% 19% 18% 17% 16% 17% Operating (Loss) / Income % (69%) (31%) (39%) (28%) (16%) (13%) (18%) All percentages for historical period are non-gaap and exclude expenses associated with stock based compensation and amortization of acquired intangibles. Please refer to the end of this presentation for a reconciliation of GAAP to non-gaap figures. 25

26 VISITOR LEAD OPPORTUNITY All-In-One Marketing & Sales Platform CUSTOMER

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Growth Strategy Large Domestic Opportunity 1 2 Large International Opportunity Upsell Customer Base 3 4 Develop New Products 28

Thank You 29

HubSpot, Inc. GAAP to Non-GAAP Reconciliation GAAP to Non-GAAP Reconciliation Year ended December 31, 2011 2012 2013 % of Revenues % of Revenues $ '000s $ '000s $ '000s $ '000s $ '000s $ '000s $ '000s Cost of Revenue Subscription* 4,964 17% 9,689 19% 18,745 24% 23,655 20% 6,940 18% 7,484 17% 8,470 18% Stock-based compensation (16) 0% (27) 0% (50) 0% (128) 0% (67) 0% (92) 0% (89) 0% Amortization of acquired intangibles (130) 0% (224) 0% (359) 0% (118) 0% (11) 0% (19) 0% (20) 0% Non-GAAP subscription* 4,818 17% 9,438 18% 18,336 24% 23,409 20% 6,862 18% 7,373 17% 8,361 18% Professional services and other 6,368 22% 6,004 12% 8,759 11% 11,425 10% 3,525 9% 3,789 9% 4,008 8% Stock-based compensation (131) 0% (100) 0% (211) 0% (498) 0% (257) -1% (347) -1% (315) -1% Amortization of acquired intangibles - 0% - 0% - 0% - 0% - 0% - 0% - 0% Non-GAAP professional services and other 6,237 22% 5,904 11% 8,548 11% 10,927 9% 3,268 9% 3,442 8% 3,693 8% Gross Profit Gross Profit* 17,221 60% 35,911 70% 50,130 65% 80,796 70% 27,701 73% 31,668 74% 35,233 74% Stock-based compensation 147 1% 127 0% 261 0% 626 1% 324 1% 439 1% 404 1% Amortization of acquired intangibles 130 0% 224 0% 359 0% 118 0% 11 0% 19 0% 20 0% Non-GAAP gross profit* 17,498 61% 36,262 70% 50,750 65% 81,540 70% 28,036 73% 32,126 75% 35,657 75% Operating Expenses Research and development 10,031 35% 10,585 21% 15,018 19% 25,638 22% 7,501 20% 8,158 19% 8,128 17% Stock-based compensation (2,341) -8% (739) -1% (691) -1% (6,190) -5% (1,633) -4% (1,629) -4% (1,568) -3% Amortization of acquired intangibles - 0% - 0% - 0% - 0% 0% - 0% - 0% Non-GAAP research and development 7,690 27% 9,846 19% 14,327 18% 19,448 17% 5,868 15% 6,529 15% 6,560 14% Sales and marketing 24,088 84% 34,949 68% 53,158 68% 78,809 68% 23,897 63% 26,291 61% 30,868 65% Stock-based compensation (647) -2% (691) -1% (1,194) -2% (5,596) -5% (2,055) -5% (2,077) -5% (1,078) -2% Amortization of acquired intangibles - 0% - 0% - 0% (20) 0% (6) 0% (7) 0% (6) 0% Non-GAAP sales and marketing 23,441 82% 34,258 66% 51,964 67% 73,193 63% 21,836 57% 24,207 56% 29,784 62% General and administrative* 7,517 26% 9,117 18% 16,204 21% 24,958 22% 7,715 20% 8,541 20% 9,527 20% Stock-based compensation (1,484) -5% (958) -2% (1,318) -2% (3,946) -3% (1,130) -3% (1,497) -3% (1,460) -3% Amortization of acquired intangibles - 0% - 0% - 0% - 0% - 0% - 0% - 0% Non-GAAP general and administrative* 6,033 21% 8,159 16% 14,886 19% 21,012 18% 6,585 17% 7,044 16% 8,067 17% % of Revenues 2014 % of Revenues Three Months Ended March 31, 2015 % of Revenues Three Months Ended June 30, 2015 % of Revenues Three Months Ended September 30, 2015 % of Revenues Loss from Operations Loss from operations (24,415) -86% (18,740) -36% (34,250) -44% (48,609) -42% (11,412) -30% (11,322) -26% (13,290) -28% Stock-based compensation 4,619 16% 2,515 5% 3,464 4% 16,358 14% 5,142 13% 5,642 13% 4,510 9% Amortization of acquired intangibles 130 0% 224 0% 359 0% 138 0% 17 0% 26 0% 26 0% Non-GAAP loss from operations (19,666) -69% (16,001) -31% (30,427) -39% (32,113) -28% (6,253) -16% (5,654) -13% (8,754) -18% * Amounts have been adjusted from prior SEC filings for reclassification of customer credit card fees from cost of revenue, subscription to general and administrative expenses to conform with current year's presentation, 30

HubSpot CRM. Say goodbye to manual tasks and confusing features. Say hello to HubSpot CRM. Stores a companies most important prospect & customer data Designed with ease of use for small companies in mind Optional integration with HubSpot s Marketing platform and Sidekick Free product anyone can use, integrates seamlessly with paid add-ons (Sidekick) Screenshot of CRM Product, March 2015. 31

Sidekick. A free, lightweight set of inbox productivity tools that sales folks will love. Track email opens & clicks, schedule emails, and leverage templates right from your inbox Surfaces useful details about the contacts & companies you are communicating with Connects to HubSpot Marketing, Salesforce or HubSpot CRM Free, $10 & $ 50 user/month versions Screenshot of Sidekick product, March 2015. 32