Where are US pennies minted?

Since 1975 circulating US cents have been minted at Philadelphia (no mint mark, even post-1980), Denver ("D" below the date) and occasionally at West Point (also no mint mark). Proof cents sold to collectors are minted at San Francisco ("S")

Earlier dates for circulation production are:

• San Francisco : 1908 to 1955 and 1968 to 1974.
• Denver : 1910 to the present
• Philadelphia : 1793 to the present