²²We measured our 2019-2024 carbon footprint, inclusive of scope 1, scope 2, and all relevant scope 3 categories, in accordance with the GHG Protocol Corporate Accounting and Reporting Standard and the Corporate Value Chain (Scope 3) Accounting and Reporting Standard. Our 2024 scope 1 and 2 emissions are verified. Starting in the 2022 footprint, we collected access swipe data across key offices to estimate the percentage of employees commuting into the office. We separately disclose optional scope 3.6 emissions from business travel accommodations and optional scope 3.7 emissions from energy usage from employees working from home. We share these categories for transparency, but they are not included in our science-based target per SBTi requirements. Scope 3.6 emissions from business travel include radiative forcing for flights. Optional scope 3.7 emissions from employees working from home are calculated using location-specific carbon intensity factors to account for differences in emission intensity of the energy sources where our employees are working from home. We acquired multiple companies between 2019 and 2022. The GHG Protocol requires that the emissions from each acquired company are included within our footprint prior to the acquisition close date starting from our base year (2019). Therefore, our acquisitions' estimated historical emissions are included in addition to our actual emissions for the applicable years. After the acquisition close date, these companies’ data are folded into our systems, and their emissions appear in our carbon footprint using more granular primary data. In line with this methodology, we restated our 2019-2023 footprints to remove ValueFirst and IoT, two business units we divested in 2023. We also added estimated emissions for 2019-2021 for our 2022 acquisition Boku. Our 2023 and 2024 market-based scope 2 emissions include Renewable Energy Certificates (RECs). We previously applied RECs to the US-based grid mix for scopes 3.3 and 3.8 for our 2021-2022 footprints, but we have removed those RECs from scopes 3.3 and 3.8 and now apply them to scope 2 in 2023. We have applied these RECs within the recommended 21-month window timeframe per Green-E guidance best practices.

For our 2024 footprint, we further improved our calculation methodologies to more accurately reflect our emissions and future-proof our reporting against evolving standards. We also restated our 2019-2023 carbon footprints using these methodology improvements. These improvements led to an increase in previously reported total emissions across each of those years. We switched from using a cash basis methodology for our operating expense data used in scope 3 to using an accrual basis methodology to improve accuracy by aligning with our audited financial statements. In prior years, our methodology utilized the U.S. Environmental Protection Agency's US Environmentally-Extended Input-Output (USEEIO) modeling, which is a single-region database. Now, our 2019-2024 footprints use the multi-region database Comprehensive Environmental Data Archive (CEDA). Covering 95 percent of global GDP, CEDA better reflects the global nature of supply chains and the complexity of goods and services production since regional energy systems and emissions profiles vary significantly. Our 2019-2024 footprints now better incorporate the latest energy estimates for cloud machine types and regional clean power in the cloud methodology, no longer incorporate region-specific power usage effectiveness values from one of our cloud computing partners in 2022-2023, more precisely attribute flight fare class to each flight leg for 2019-2022, more accurately categorize a small portion of spend as goods and services instead of travel, better incorporate a more comprehensive estimate of acquired companies' historical emissions, now include well-to-tank emissions for commute and home offices, and generally benefit from improved data availability and updated emission factors. As we continuously improve our calculation methodologies, we continue to track progress against and review our science-based targets.

²³ Energy consumption is defined as electricity usage and all other energy types. We have restated our 2019-2023 energy consumption in line with the changes described above for our footprint. We have also restated our 2019-2023 scope 2 energy consumption to include purchased/acquired heat, but this is not included in the percentage renewable out of Scope 2 electricity measure since that takes into account electricity only. Emissions calculated from acquisitions leveraged a methodology that did not include primary energy consumption data as an input, and this data was not otherwise available. Therefore, energy consumption quantities for acquired companies have been excluded from the energy use table.

²⁴ Estimated water use is calculated for offices based on internal records and utility bills where available. For offices where water consumption data is unavailable, we estimate water use by applying an average water use (m3) per square foot based on available data for other offices we lease. These estimates are for freshwater use only and are calculated based on the square footage of all offices we leased during the year. We restated our 2022-2023 water consumption estimates based on new water utility information for our San Francisco Spear Street office and Sydney office.

²⁵ The percentage is calculated based on the square footage of our San Francisco Spear Street office, which is LEED Gold certified, relative to the total square footage of all offices we leased during the year. We do not own any real property.

²⁶ Metric language is pulled directly from the SASB standards for the Software & IT Services industry.

²⁷ Rather than providing data on foreign nationals, we are providing information on all employees by region. In the US, we follow US Equal Employment Opportunity Commission (EEOC) guidelines in how we track employee data. In all other countries where we operate, we follow region-specific data privacy guidelines in how we track employee data. All employee data is pulled from Twilio’s Workday system as of December 31, 2024. This data includes regular and fixed-term employees only. This data includes employees that are fully integrated with Twilio and will exclude non-integrated employees until the year that they are integrated. Mexico is designated as part of Latin America.

²⁸ This score is based on employee ratings for the statement, “I would recommend Twilio as a great place to work.” Results are as of Q4 2022 for 2022, Q3 2023 for 2023, and an average of all four quarters for 2024. In 2022 and 2023, we conducted an annual employee engagement survey, and starting in 2024 we implemented a new quarterly cadence for surveying employees. After we survey employees, we share the results internally and refocus our work based on employee feedback.