#1Dexcom Dexcom Investor Presentation September 2023 CONFIDENTIAL - DO NOT DISTRIBUTE#2Safe Harbor Statement Dexcom This presentation contains "forward" looking statements that are based on our management's beliefs and assumptions and on information currently available to management. We intend for such forward-looking statements to be covered by the safe harbor provisions for forward-looking statements contained in the U.S. Private Securities Litigation Reform Act of 1995. Forward-looking statements include information concerning our possible or assumed strategy, future operations, financing plans, operating model, financial position, future revenues, gross margin, operating margin, projected costs, competitive position, industry environment, potential growth opportunities, potential market opportunities, plans and objectives of management and the effects of competition on our business. This presentation also contains estimates and other statistical data made by independent parties relating to market size and growth and other data about our industry. This data involves a number of assumptions and limitations, and you are cautioned not to give undue weight to such estimates. Forward-looking statements include all statements that are not historical facts and can be identified by terms such as "anticipates," "believes," "could," "seeks," "estimates," "targets," "guidance," "expects," "intends," "may," "plans," "potential," "predicts," "prospects," "projects," "should," "will," "would" or similar expressions and the negatives of those terms, although not all forward-looking statements contain these identifying words. Forward-looking statements involve known and unknown risks, uncertainties and other factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements. We cannot guarantee that we will achieve the plans, intentions, or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. The risks and uncertainties that may cause actual results to differ materially from our current expectations are more fully described in our annual report on Form 10- K for the period ended December 31, 2022, as filed with the Securities and Exchange Commission on February 9, 2023, our most recent quarterly report on Form 10-Q for the period ended June 30, 2023, as filed with the Securities and Exchange Commission on July 27, 2023, and our other reports, each as filed with the Securities and Exchange Commission. We assume no obligation to update any such forward-looking statement after the date of this presentation or to conform these forward-looking statements to actual results. We report non-GAAP financial measures in addition to, and not as a substitute for, or superior to, measures of financial performance prepared in accordance with GAAP. These non-GAAP financial measures are not based on any comprehensive set of accounting rules or principles, differ from GAAP measures with the same names, and may differ from non-GAAP financial measures with the same or similar names that are used by other companies. We believe that non-GAAP financial measures should only be used to evaluate our results of operations in conjunction with the corresponding GAAP financial measures. We encourage investors to carefully consider our results under GAAP, as well as our supplemental non-GAAP information and the reconciliations between these presentations, to more fully understand our business. 2#3Our Mission: Empowering people to take control of health Dexcom 127 3#4FY23 Guidance 2023 Outlook as of July 27, 2023 Objectives & Considerations • • Global rollout of G7 Expansion of Dexcom ONE into new geographies • Building momentum in type 2 basal Strong year-over-year operating expense leverage Revenue of $3.500 - 3.550 billion (~20-22% Growth) Gross Margin of ~63% Operating Margin of ~17% Adjusted EBITDA Margin of ~26.5% We expect global momentum to build in 2023 and create a foundation of growth for years to come Dexcom 4#5A Global Crisis that Remains Uncontrolled Diabetes Diagnosis and Cost Adults (aged 20-79) with Diabetes Globally 151m in 2000 Source: IDF Atlas, 10th edition (2021) Dexcom 463m in 2019 537m in 2021 783m in 2045E Global Diabetes Related Health Expenditures USD 760b 2019 +27% increase Past 2 Years USD 966b 2021 5#6Glucose (mg/dl) 340 320 300 280 260 240 220 200 180 160 140 120 100 80 60 40 20 0 0 2 4 Intermittent glucose monitoring is not enough for intensive insulin management... Target Glucose Range CO 6 8 00 Dexcom *As compared to Self Monitoring of Blood Glucose (SMBG) ☑ SMBG* 22 22 20 10 12 14 16 18 20 Time (hours) 24 24 6#7Intermittent glucose monitoring is not enough for intensive insulin management... Glucose (mg/dl) 340 320 300 280 OVER 4 HOURS ABOVE 210 BEFORE SMBG* 260 240 220 ABOVE 140 FOR 13.5 HOURS 200 180 160 140 120 100 Target Glucose Range 80 60 40 DANGEROUS LOW FOR 1 HOUR 20 0 0 2 4 6 8 10 12 14 16 18 20 22 20 Time (hours) Dexcom *As compared to Self Monitoring of Blood Glucose (SMBG). Illustrative example. 22 24 7#8...and non-intensive type 2 diabetes management Glucose (mg/dl) 340 320 300 280 260 240 220 200 180 160 140 120 100 80 60 40 20 0 0 2 4 Target Glucose Range ☑ SMBG* 22 22 20 CO 6 8 10 12 14 16 18 20 Time (hours) Dexcom *As compared to Self Monitoring of Blood Glucose (SMBG). 24 8#9Glucose (mg/dl) APPROXIMATELY 17 HOURS ABOVE TARGET RANGE, INCLUDING 6 HOURS IN SEVERE HYPERGLYCEMIA (>250 mg/dl) 340 320 300 280 260 240 220 ...and non-intensive 200 180 type 2 diabetes 160 140 management 120 100 80 60 40 20 0 0 2 4 AVG GLUCOSE: 185 mg/dl Target Glucose Range CO 6 8 10 12 Time (hours) 14 16 18 20 20 Dexcom *As compared to Self Monitoring of Blood Glucose (SMBG). Illustrative example drawn from a pilot program involving Dexcom CGM use in Type 2 NIIT. 22 22 24 24 6#10Dexcom 10:30 Dexcom *50% 6.1 → mmol/L 22 18 -14.0 3.9 08 09 10 Now 3 Hours AV Menu O 10:30 Dexcom 6.1 mmol 3 Hours 6 12 24 -22 ................ -14.0 སྤུ་ྋ བ་༠ -18 3.9 -2 Now Clarity (i) 3 Days 7 14 30 90 同 Glucose History Connections Dexcom Dexcom We can do more 10#11Connectivity as a Competitive Advantage Differentiating through hardware and software 110 Dexcom G7 Dexcom Dexcom One Dexcom one 0000 Dexcom G6 Customers Automated Insulin Delivery Connected Pen TANDEMⓇ DIABETES CARE Lilly Insulet™ Loved Ones Dexcom one Follow App A Digital Health Apps GARMIN novo nordisk SIGNOS 1. LEVELS Healthcare Providers 山 Clarity Clinic glooko 11#12Dexcom G7 110-> mg/dL R Dexcom 1. 10:30 10:30 Dexcom 110 mg/dL 3 Hours 6 12 24 ・・・・ -400 10 -250 -70 -40 58 Now Clarity i 3 Days 7 14 30 90 ל Glucose History Connections Pre Dexcom Dexcom, data on file, 2023. Dexcom G7 is the new standard in CGM technology Dexcom 00 Most Accurate 1 Incredible Simplicity Engaging#1310:30 Dexcom 10:30 Dexcom 110▸ mg/dL 3 Hours 6 12 24 * 50% 110→ mg/dL 400 250 08 09 10 Now 3 Hours AV Menu O S Clarity Now 400 -250 -70 40 3 Days 7 14 30 90 15 Glucose History Connections Dexcom G7 Is Living up to its High Expectations DIRECT FEEDBACK ፡፡ I basically forgot it was there... that is the dream, really. For me, it is definitely a big step forward in terms of comfort and convenience. Dexcom CE We are obsessed with how quickly the sensors warm up, in just 30 minutes! GE Once it was on and in, I didn't know it was there at all. I can't praise it enough. 97% of new customers surveyed find G7 easy to use¹ Dexcom 1. Dexcom market research during initial launch phase 13#14What's Next for G7? ④ International Markets Extending launch to additional geographies: We are fully launched in 13 markets Expanding into additional regions in the coming months Dexcom 1. Dexcom, data on file, 2022 + Building Access Established reimbursement for G7 in US across our channels Commercial DME • Medicare Commercial pharmacy Quickly built broad reimbursement by mid- 2023 • Expanding Connected Solutions Leveraging world's most connected CGM ecosystem 1 to bring more choice to users Connected to several digital health apps at launch • Working with pump and pen partners to integrate G7 into insulin delivery systems 14#15Core US Market S Momentum and opportunity remain significant With coverage for basal insulin users and problematic hypoglycemia there is more people with access to CGM than ever before Dexcom Insulin & Non-Insulin Hypoglycemia Population 2016 2017 2018 2019 2020 2021 2022 CMS Basal CMS Hypo Commercial Coverage Coverage Basal (60%+) Estimated US IIT CGM Users - All companies* Estimated Reimbursed Population* T1 Commercial + Medicare (T1 + T2 IIT) + Medicaid + T2 IIT Commercial *Dexcom market research and Wall Street research. Estimated Reimbursed Population based on Dexcom market research. Basal-Only & Problematic Hypo All Insulin ~7m IIT ~4m 15#16Commercial Access Efforts Empower our Customers Meeting our customers where they want to be met in either the pharmacy or durable medical equipment channels 肆 Simple to Prescribe Broad Customer Access Efficient Service Model Dexcom is the number one covered and most reimbursed CGM on the market¹ Dexcom 1. Managed Markets Insights & Technology, LLC. MMIT Analytics, June 2022 16#17Commercial Execution Growing presence within primary care STRATEGIC INITIATIVES 01 Drove reimbursement through clinical evidence (MOBILE study) 02 Doubled size of sales force in 2021 03 Introduced sampling program to highlight the Dexcom experience 04 Empowered sales team with digital tools Over the past two years1: We doubled total primary care prescriber base We doubled the average monthly new patients starting in primary care Dexcom 1. Data reflects year-end 2022. 17#18Gaining Market Share Internationally Dexcom Entering new geographies Reducing administrative barriers Gaining reimbursement Leveraging e-commerce platform Well-positioned to extend growth momentum OUS Going direct in strategic markets 18#19Dexcom's Portfolio Strategy: Meeting the Needs of Each Market Broad Reimbursement 110 110➤ 2 Hours 6 24 400 Clarity Days 1 10 Now 256 1 14 30 E •рехсот 110- 10:30 Tiered Reimbursement Markets 110➤ 3 Hours 6 12 24 40 9 10 Now Clarity 0 1 Days 7 14 30 50 回 5 • G-Series Leading Accuracy & Connectivity G-Series Connected & Higher- Risk Populations Dexcom Dexcom one Dexcom one Dexcom ONE Limited Reimbursement • Simple & Accurate • Dexcom Dexcom ONE 3 Month Bundle Dexcom ONE E-Commerce Accessibility 19#20OUS Markets Significantly improving access We have successfully expanded coverage for G-Series and Dexcom ONE Dexcom Access for 3.5 million additional people with diabetes over the past 18 months (year-end '22) UK Spain Germany Canada Australia Japan Other Countries #+ *Estimated Reimbursed Population based on Dexcom market research. 20 20#21Type 2 Diabetes 3 Elements of an Effective Solution Dexcom میرا User Engagement Health Outcomes Return on Investment 21 21#22Type 2 Diabetes: 3 Elements of an Effective Solution میرا User Engagement Sustained engagement demonstrated in non-intensive studies Example: MOBILE results suggested patient engagement was the most likely source of improved glycemic control¹ Health Outcomes Evidence generation through clinical trials, real-world evidence, and pilots with key partners Example: Recent study demonstrated broad cardiometabolic outcomes with improved glucose control² Return on Investment Strong economic return to payers Example: Multiple studies demonstrate cost savings per member per month of $400+3,4 1. https://jamanetwork.com/journals/jama/article-abstract/2780595 2. Majithia et al., "Glycemic Outcomes in Adults With Type 2 Diabetes Participating in a Continuous Glucose Monitor-Driven Virtual Diabetes Clinic: Prospective Trial," JMIR 22:8 (2020). 3. Compared to SMBG cohort. For the published results see Isaacson B, Kaufusi S, Sorensen J, et al. Demonstrating the Clinical Impact of Continuous Glucose Monitoring Within an Integrated Healthcare Delivery System. JD ST. September 2020. 4. Includes real-world claims data for a combination of Type 2 intensive and non-intensive Dexcom customers. Link here Dexcom 22 22#23Across All Segments of T2D, CGM Use Increases with GLP-1 Initiation % CGM usage for those initiating GLP-1 therapy in each year Type 2 Intensive Insulin Average CGM Increase: 2.0x CLINICAL DRIVERS OF CGM USE WITH GLP-1 Provides insights and behavior modification required for long-term metabolic health 40.0% 30.0% 20.0% 10.0% 0.0% 2018 2019 20.0% 15.0% 10.0% 5.0% 0.0% 2018 2019 6.0% 4.0% 2.0% 0.0% 2018 2019 Dexcom 2020 2021 Type 2 Basal Insulin Only Average CGM Increase: 3.8x 2020 2022 Supports dose titration for therapeutic regimen, as recommended in GLP-1 labeling Helps enable durability of health outcomes 2021 2022 Type 2 Non-Insulin Therapy Average CGM Increase: 4.2x % Users on CGM prior to initiating GLP-1 2020 2021 2022 % Users on CGM after initiating GLP-1 Source: Optum Payer Claims Database, includes commercial and Medicare Advantage members. Increasing access and simplicity of CGM systems supports continued acceleration of CGM adoption across all T2D segments, including with GLP-1 use 23#24Our Mission: Empowering people to take control of health Dexcom Where We Are . Type 1 . Type 2 IIT Where We Are Going • • Type 2 Non-Insulin Pre-Diabetes Type 2 Basal-Only • Gestational Diabetes Type 2 Problematic Hypo (Non-Insulin) • Patient Monitoring • Health & Wellness 24 24#25月 RIP CURL This is our W KEEP 409 CALM AND CARRY DEXCOM 906 KEEP CALM AND CARRY EXCOM Dexcom DEX REX my GRL POWER 3