^{6 Based on an operational control approach, as defined by WRI GHG Protocol and scope guidance. Boundaries include all material operating locations.} 

^{7 Where actual consumption data was not available, we used a sampling approach or public information, such as equipment fuel efficiency and power ratings, to estimate fuel and energy consumption.}

^{8 Electricity consumption and resulting emissions associated with HVAC systems situated in ground shelters at our tower sites are calculated based on the applicable energy consumption factors for each type of HVAC unit (e.g., central air, window unit, etc.) that was in operation in 2023 at such sites, taking into account assumptions regarding (i) customer tenancy at company-owned shelters, (ii) customer reliance (or lack thereof) on our HVAC units and (iii) HVAC system operations in unoccupied shelters}

^{11 Based on estimated allocation between diesel and gasoline vehicles.}

^{12 Refrigerant estimates were determined using vehicle data, active HVAC unit data, and assumed refrigeration and HVAC systems in office and warehouse spaces, based on square footage, using the EPA’s Accounting Tool to Support Federal Reporting of Hydrofluorocarbon Emissions: Supporting Documentation (Oct. 2016).}

^{13 Based on an operational control approach, as defined by WRI GHG Protocol and scope guidance. Boundaries include all material operating locations.}

^{14 We used emission factors from 40 CFR Part 98 Tables C-1 and C-2 and EPA eGRID factors. Global Warming Potential documented in the Intergovernmental Panel on Climate Change AR5 report was used to calculate CO2 e for methane (CH4 ) and nitrous oxide (N2 O).}

^{15 Our 2022 and 2023 Scope 2 emissions were calculated using WRI GHG Protocol’s market-based method. Prior years’ Scope 2 emissions calculations were reported using WRI GHG Protocol’s location-based method. Refer to the ESG Data Tables for Scope 2 emissions calculated using the location-based method covering the years indicated therein.}

^{16 Scope 3 emissions were calculated using the Corporate Value Chain (Scope 3) Accounting and Reporting Standard: Supplement to the GHG Protocol Corporate Accounting and Reporting Standard. Scope 3 emissions quantification is subject to significant inherent measurement uncertainty due to the emissions being outside of Crown Castle’s organizational boundaries, where the company has limited control over the availability of primary data. Additionally, uncertainties arise from (1) using GHG emissions factors, which are themselves estimates, in mathematical models for calculating emissions and (2) the models' inability, due to incomplete scientific knowledge and other factors, to precisely measure the relationship between various inputs and the resultant GHG emissions in all scenarios.}

^{17 Scope 3 emissions from Category 13: Downstream Leased Assets were calculated separately for tower, small cell, and fiber customers, with emissions across all three asset types calculated by zip code to align with the correct eGRID regions. For tower customers‘ energy use, an average data method was used that estimated annual consumption per tower for each of our largest customers individually and grouped similar smaller customers together based on their anticipated energy use profiles. These estimates were validated with a sample of our largest customers. Where applicable, customer renewable energy contributions were factored in to reduce market-based emissions, using publicly reported data. For small cell customers, average equipment electricity use was estimated based on device type and location. For fiber customers, average energy consumption calculations were based on service type and speed.}

^{18 Scope 3 emissions from Category 1: Purchased goods and services and Category 2: Capital goods were calculated using the spend-based method based on the economic value of goods and services purchased or acquired as recorded in Crown Castle’s financial reporting system. Certain spend categories, such as taxes, land rent, and payroll-related spend, are not included in the analysis because Crown Castle determined that there are not significant emissions associated with the spend. Total category spend was multiplied by the corresponding NAICS emissions factors from NAICS v1.2 (2022), adjusted for inflation.}

^{19 Other Scope 3 emissions include categories that Crown Castle believes are individually less material to our overall footprint but are relevant to our operations, including fuel- and energy-related activities, upstream transportation and distribution, waste generated in operations, business travel, employee commuting, and upstream leased assets. Refer to the ESG Data Tables for our comprehensive emissions inventory and additional detail regarding the calculation approaches utilized.}

^{21 Water is reported for Crown Castle’s owned office locations. Office closures stemming from Covid-19 and changes in our hybrid work schedule impacted the comparability of our water utilization from 2020 to 2023; as such, we have elected to present a single year of water consumption data.}

^{22 The actual water consumption data for the Albany office in 2023 was unavailable, so we estimated it based on the 2022 figures, adjusted for employees working four days a week in the office in 2023 compared to three days in 2022.}

^{24 We used emissions factors from U.S. EPA, 2023, Emission Factors for Greenhouse Gas Inventories, Table 9 (waste).}