Военные сберегательные марки США в Первой и Второй мировых войнах.

War savings stamps were issued by the United States Treasury Department to help fund participation in World War I and World War II. Although these stamps were distinct from the postal savings stamps issued by the United States Post Office Department, the Post Office nevertheless played a major role in promoting and distributing war savings stamps. In contrast to Liberty Bonds, which were purchased primarily by financial institutions, war savings stamps were principally aimed at common citizens. During World War I, 25 cent Thrift stamps were offered to allow individuals to accumulate enough over time to purchase the standard 5 dollar War Savings Certificate stamp. When the Treasury began issuing war savings stamps during World War II, the lowest denomination was a 10 cent stamp, enabling ordinary citizens to purchase them. In many cases, collections of war savings stamps could be redeemed for Treasury Certificates or War Bonds.

The United States Treasury Department issued its first war savings stamps in late 1917 in order to help pay for the costs incurred through involvement in World War I. The estimated cost of World War I for the United States was approximately $32 billion, and by the end of the war, the United States government had issued a total of $26.4 billion in debt. Although national campaigns had aimed to sell $2 billion in war savings stamps, they ultimately accounted for about $0.93 billion, or 3.5 percent, of the total debt issued. Despite the low proportion of total debt purchased as war savings stamps, they represented real additional savings whereas other issues were at least partly monetized already.

Along with the War Savings Certificate stamps, the Treasury also issued a set of 25 cent Thrift stamps, which bore no interest. The purpose of the Thrift stamps was to allow individuals without the means to purchase a War Savings Certificate stamp outright to gradually accumulate enough Thrift stamps to exchange for one later. The Treasury supplied Thrift cards, to which a total of sixteen Thrift stamps could be affixed. A full Thrift card was worth four dollars and could be combined with the appropriate number of cents to purchase a War Savings Certificate stamp.

Promotion of war savings stamps pervaded American culture during World War I. The Treasury Department established the War Savings Organization in order to coordinate marketing efforts throughout the nation. Governors, mayors, and other political leaders led by example by purchasing war savings stamps and encouraged their constituents to do the same. The Four Minute Men organization, authorized by President Wilson, also developed a series of speech outlines related to war savings stamps for its volunteers to deliver. Support for war savings stamps also came from a variety of non government sources. Advertisements were often donated by local newspapers in order to inform people of how war savings stamps worked and to encourage their purchase. War savings societies formed within communities across the country to promote the value of thrift and to collect funds for war savings stamps. Children were also recruited to the war saving efforts primarily through their schools. Children received school kits, which included penny and nickel savings booklets so that children could save up for a 25 cent Thrift stamp a few cents at a time.

The promotion of war savings stamps during World War II was closely tied with the promotion of the Series E war bonds. In order to mobilize the home front to support the war efforts ideologically and financially, the Treasury Department's primary message revolved around patriotism. With support from the advertising industry, which donated $250 million worth of advertising during the first three years of the campaign, war bonds and stamps permeated everyday life. Advertisements appeared as posters on trolley cars, songs on the radio, and movies featuring Hollywood stars like Frank Sinatra and Bob Hope.

During World War II, the Mennonite Central Committee offered red Civilian Public Service stamps and blue War Sufferers' Relief stamps for ten cents each to help fund peaceful programs and offer an alternative for children from families who could not conscientiously fund the Red Cross. The Brethren in Christ had a similar program for their members.