Reserve (sometimes Reserves) may refer to:
- Official gold reserves, held by central banks as a store of value
- Foreign exchange reserves, the foreign currency deposits held by central banks and monetary authorities
- Reserve currency, a currency which is held in significant quantities as part of foreign exchange reserves
- Strategic Petroleum Reserve, an emergency petroleum store maintained by the U.S. Department of Energy
- Fractional-reserve banking
- Bank reserves, holdings of deposits in central banks plus currency that is physically held in bank vaults
- Reserve (accounting), any part of shareholders' equity, except for basic share capital
- Reserve (project management), an element of the total project budget provided for realized project changes
- Mineral reserves, natural resources that are economically recoverable, e.g. Oil reserves
- Actuarial reserves, a liability equal to the present value of the future expected cash flows of a contingent event
- Reserve Primary Fund, a money market fund which "broke the buck"
- Auction Reserve, a minimum amount of money bid required for a sale in an English auction
- Military reserve, military units not initially committed to battle
- Military reserve forces, are units formed of military personnel making a long term commitment to train part-time and maintain military skills.
- Reserve components of the United States armed forces, "the Guard and Reserves"
- Primary Reserve component of the Canadian Forces
- War Reserve Stock, a collection of war fighting material held in reserve in pre-positioned storage to be used if needed in wartime
- Regular Army Reserve of Officers, British Army officers holding regular commissions who are in receipt of retired pay and are held on the strength of the Regular Army until they reach the age of fifty five. RARO officers retain their rank and commissions and are liable for recall to active duty as required by the Ministry of Defence.
- Game reserve, land set aside for maintenance of wildlife for tourism or hunting
- Indian reserve, in Canada, a tract of land reserved for the use and benefit of a band
- Nature reserve, a protected area of importance for wildlife, flora, fauna or features of geological or other special interest
- Reserve clause, in North American professional sports contracts
- Reserve team, the second team fielded by a sports club, often football-soccer
In the United States:
- Reserve wine, a wine that specially designated
- Course reserve, library materials reserved for particular users
- Dynamic reserve, the set of metabolites that the organism can use for metabolic purposes
- Fuel reserve, an extra fuel tank, or extra fuel in the main fuel tank
- Recreation reserve, a park with sporting or other recreational facilities
- Stockpile, a reserve of bulk materials for future use
- Reserved decision, where a judge takes time to review evidence and the law and delivers a decision at a later time