Numistify guide
Key Date Coins: What They Are and Which Ones to Look For
In every popular series, a few dates are much harder to find than the rest, and collectors pay accordingly. Here is what makes a key date, the ones worth knowing, and why they are also the coins most often faked.
The short answer
A key date is a date, or date and mint mark, that is much harder to find than the others in its series — usually because few were struck, few survived, or few survive in good condition. The best-known Lincoln wheat cent key dates are the 1909-S VDB, 1909-S, 1914-D, 1922 No D and 1931-S, plus the 1955 doubled die.
What a key date is
A key date is a date — or a date and mint mark combination — that is much harder to find than the others in its series. The next level of difficulty down are called semi-key dates. Completing a set means finding the keys, which is why they command premiums even in worn condition.
What makes a key date
Low mintage. The usual cause. The 1916-D Mercury dime had a mintage of 264,000, against about 22 million for the 1916 from Philadelphia.
Low survival. Coins struck in reasonable numbers can still be scarce if most were melted, lost or worn away.
Condition. Some dates are common worn but scarce in high grades. The 1934-S Peace dollar had a mintage of over a million, yet fewer Mint State examples are known than of any other date in the series.
Demand. A key date matters because many people collect the series. A scarce coin in a series nobody collects does not command the same premium.
Key dates in popular US series
| Series | Years | Key dates |
|---|---|---|
| Lincoln wheat cent | 1909–1958 | 1909-S VDB, 1909-S, 1914-D, 1922 “No D”, 1931-S; the 1955 doubled die |
| Buffalo nickel | 1913–1938 | 1913-S Type 2, 1916/16 doubled die, 1926-S, 1937-D “three-legged” |
| Mercury dime | 1916–1945 | 1916-D, 1921, 1921-D, 1942/1 overdate |
| Standing Liberty quarter | 1916–1930 | 1916, 1918/7-S |
| Washington quarter | 1932– | 1932-D, 1932-S |
| Walking Liberty half dollar | 1916–1947 | 1916-S, 1921, 1921-D, 1921-S, 1938-D |
| Morgan dollar | 1878–1921 | 1889-CC, 1893-CC, 1893-S, 1894, 1895 (proofs only), 1895-O |
| Peace dollar | 1921–1935 | 1921, 1928, 1934-S |
Two notes. The 1928 Peace dollar has the lowest mintage in its series, at 360,649. The 1895 Morgan dollar was struck only as a proof, so collectors who want the date buy a proof.
Condition still matters
A key date in poor condition is still a key date, but the grade makes a large difference to value. A worn but problem-free key is often more desirable than a sharper one that has been cleaned or damaged. Our guide to coin grades explains the scale.
Fakes and alterations
Because they are valuable, key dates are the coins counterfeiters target most. Many fakes are altered genuine coins: a D added to a common 1916 dime, an S and VDB added to a 1909 cent, a 1917 Standing Liberty quarter tooled into a 1916. Buy valuable key dates certified by PCGS or NGC, and check the certification number. Our guide to spotting fake coins shows what to look for.
Finding the value
Key date prices vary widely with grade. Look the coin up in the Red Book, compare historical auction prices and eBay sold listings for the same date in the same grade, and ask your local coin shop. Our guide to what your coin is worth walks through each step.
Questions people ask
What is a key date coin?
A date, or date and mint mark combination, that is much harder to find than the others in its series. The next level down are called semi-key dates.
What makes a coin a key date?
Usually a low original mintage, but also how many survived, how many survive in good condition, and how much collectors want the series. A coin struck in large numbers can still be scarce in high grades.
What are the key dates for Lincoln wheat cents?
The best known are the 1909-S VDB, 1909-S, 1914-D, 1922 No D and 1931-S, plus the 1955 doubled die.
What are the key date Morgan dollars?
Among the best known are the 1889-CC, 1893-CC, 1893-S, 1894 and 1895-O, and the 1895, struck only as proofs.
Are key date coins often counterfeited?
Yes. Key dates are the main targets of counterfeiters and of altered coins, such as a common date with an added mint mark. Buy valuable key dates certified by PCGS or NGC.
Related guides
How to tell if a coin is valuable — key dates among the other signs of value.
Where is the mint mark? — the letter that often makes the key.
Own a few of these?
Numistify is where collectors keep track of what they actually have — coins, banknotes and bullion in one catalogue, with the date, mint mark, grade and cert number on every piece.
It also works out what each item really cost you, with the buyer fees, shipping and grading added in rather than just the hammer price. When you sell, you can see what you made on it.
Free for your first 50 items, and there is no card to enter.