TDA may refer to:

Finance Tax deferred annuity, a type of retirement plan under IRC Section 403(b) Time deposit account TreasuryDirect account, an account used to buy securities from the US Treasury "Treasury Direct Account," a fraud scheme promoted in the redemption movement

Organizations Tautinio Darbo Apsaugos Batalionas, auxiliary police unit In Lithuania in 1941 Team Disney Anaheim, the administrative headquarters of the Disneyland Resort in California Télédiffusion d'Algérie, an Algerian public service broadcasting and internet service provider Texas Department of Agriculture Thomas Deacon Academy, a city academy in Peterborough Toa Domestic Airlines, later known as Japan Air System Tournament Directors Association, an organization that works to standardize poker tournament rules worldwide Training and Development Agency for Schools, a defunct British teacher training program Tren de Aragua, a Venezuelan criminal organization United States Trade and Development Agency

Television The Disney Afternoon, a two-hour television programming block Total Drama Action, the second season of Total Drama

Chemistry Tris(2-(2-methoxyethoxy)ethyl)amine Toluenediamine

Other TDA, ISO 639-3 code for the Gadal language Taking and driving away, a term for auto theft under Scottish law Tamm–Dancoff approximation, a method used in many-body theory Temporary duty assignment, a United States Government employee travel assignment Table of distribution and allowances, a temporary type of US Army TOE Topological data analysis Tornado detection algorithm, the replacement of the tornado vortex signature (TVS) Traditional double action, a style of semi-automatic pistol action, also known as DA/SA