What Is a Key Date?
A key date is the scarcest or most sought-after date and mint mark combination in a coin series. It is usually the hardest to find, the most expensive, or the one needed to complete a set. Key dates are not always the lowest mintage in a series, as survival rates, demand, and historical interest also play a role. Collectors sometimes also use “semi-key” for dates that are harder to find than most but less costly than the true keys.
Understanding key dates also means understanding mint marks on coins, since many keys depend on which mint struck them.
Well-Known Key Dates by Series
Mintage figures below are approximate and drawn from standard references. Check a current Red Book for exact numbers.
Lincoln Cents
- 1909-S VDB: The first-year cent with the designer’s initials on the reverse, struck in San Francisco. Mintage was roughly 484,000.
- 1914-D: A Denver cent with a mintage a little over a million, very scarce in higher grades.
- 1931-S: Lower mintage than neighboring years, around 866,000.
Indian Head and Flying Eagle Cents
- 1877 Indian Head cent: Mintage of about 852,500, the series key.
- 1856 Flying Eagle cent: A small number were struck as patterns and then sold to collectors; demand has made it a popular rarity.
Nickels and Dimes
- 1913 Liberty Head nickel: Five known, not officially issued. Far outside normal budgets.
- 1916-D Mercury dime: Denver mintage around 264,000, the series key.
- 1894-S Barber dime: Only 24 were struck, and fewer than that are known today.
Quarters
- 1916 Standing Liberty quarter: Mintage around 52,000.
- 1932-D and 1932-S Washington quarters: Both low-mintage, with figures around 436,800 and 408,000, widely viewed as keys of the series.
Silver Dollars
- 1893-S Morgan dollar: Mintage of 100,000, with few high-grade survivors.
- 1895 Morgan dollar: Business strikes are generally considered not to exist, and proofs are the known coins. Be very cautious of any offered as circulation strikes.
- 1804 dollar: Often called the king of American coins, though issued later than its date. Only a small number exist.
Why Condition Matters
Key dates are expensive even in worn condition, and the price jump from a lower to a higher grade can be large. Many collectors buy a lower-grade original example rather than not owning one at all. A coin that has been cleaned or damaged will normally sell at a discount.
Beware of Fakes and Altered Dates
Key dates are among the most counterfeited coins. Common tricks include adding or removing a mint mark and altering a date. Before buying:
- Buy from reputable dealers who offer return rights.
- Prefer coins certified by a major grading service for expensive purchases.
- Learn how the genuine mint mark looks (shape, spacing, and position).
What Coins Should I Look For in 2026?
Interest in a new year usually focuses on the Mint’s release schedule, special finishes, and any reported errors, and these details change throughout the year. Check the US Mint’s own announcements and current numismatic news for what has been issued and whether any 2026 coins are available, rather than relying on older articles. Current-year coins generally have no key-date status, because key dates need time to emerge from mintage and survival data.
Building a Set with Key Dates
If you are working toward a full date-and-mint-mark set, consider leaving the key date for last. The rest of the set will teach you what to look for. For help deciding on a series in the first place, see the best coins to collect or coin collecting 101. Scarcer coins at the extreme end are covered in the rarest coins in the world.