U.S. mint marks

1793–present (mark used 1942–1945 on nickels, then 1979–present on most coins) · The original US Mint. It struck coins with no mint mark for most of its history; the P mark first appeared on WWII silver nickels and became standard on most denominations from 1979–1980 on. Cents from Philadelphia still carry no mark.

1906–present · The workhorse of modern circulating coinage — Denver often strikes more coins per year than any other mint. Don't confuse it with the earlier Dahlonega 'D' on pre-Civil War gold coins.

1854–present · Born in the Gold Rush. It struck circulating coins into the 1950s and again briefly in the late 1960s–70s, but since 1975 the S mark mostly means proof coins made for collectors.

1984–present · Mainly strikes bullion and collector coins (gold, silver, platinum). W-mark quarters were released into circulation in 2019–2020 as a treasure hunt — they're scarce and worth pulling from change.

1838–1861, 1879–1909 · A major branch mint of the 1800s, closed around the Civil War and again for good in 1909. Found on Morgan dollars, Barber coinage, and other classics — an O mark means the coin is over a century old.

1870–1893 · The romantic one: a small Nevada mint that coined Comstock Lode silver. CC coins, especially Morgan dollars, carry big collector premiums almost regardless of condition. The only two-letter US mint mark.

1838–1861 · A tiny North Carolina branch mint that struck ONLY gold coins from local ore. All Charlotte coins are scarce and collectible; you will not find one in change, but you may meet one in an inheritance.

1793–present · For most of US history, no mint mark meant Philadelphia. This is why a blank spot where you expected a letter is usually normal, not an error — check whether that series even used a P before assuming a missing mint mark.