D
- Data transmission
- Deadweight loss
- Debentures
- Debt
- Decatherm
- Decommissioning
- Decoupling
- Decoupling of revenue and output
- Decreasing returns
- Decreasing returns to scale
- Decreasing-cost industry
- Deep discounting
- Deflator
- Degree day
- Demand
- Demand curve
- Demand curve, movements along
- Demand side management
- Demand, annual maximum
- Demand, annual system maximum
- Demand, average
- Demand, billing
- Demand, charge
- Demand, coincident
- Demand, instantaneous peak
- Demand, law of
- Demand, maximum
- Demand-based pricing
- Demerit goods
- Demographics
- Dependability
- Depreciation
- Deregulation
- Derivatives
- Derived demand
- Detailed Valuation Methodology (DVM)
- Developed countries
- Developing countries
- Deviation
- Dial tone
- Differentiated products
- Digital Subscriber Line (DSL)
- Digital Subscriber Loop Multiplex (DSLAM)
- Digital transmission
- Diminishing returns
- Direct access
- Direct connection
- Direct costs
- Direct Load Control (DLC)
- Directory
- Directory assistance
- Directory Assistance System (DAS)
- Disaggregation
- Disbursement
- Disclosure regulation
- Disclosures
- Disconnection
- Disconnection notice
- Discount plan
- Discount rate
- Discounted cash flow
- Discriminating monopoly
- Diseconomies of scale
- Diseconomies of scope
- Disequilibrium
- Dispatch, Dispatching
- Distributed Generation
- Distribution
- Distribution channel
- Distribution Company
- Distribution line
- Distribution of income
- Distribution service
- Distribution utility (Disco)
- Disutility
- Diversifiable risk
- Diversification
- Divestiture
- Division of labor
- Dominant carrier
- Dominant firm
- Dominant strategy
- Duopoly
- Durable good