What Is a Special Mint Set (SMS)?
If you collect modern U.S. coins, you may have come across the term Special Mint Set, often abbreviated as SMS. These sets were produced for only a short period in U.S. Mint history, yet they remain an interesting and sometimes misunderstood part of coin collecting.
Special Mint Sets were issued by the United States Mint between 1965 and 1967, during a time of major change in American coinage. They were created as a temporary replacement for both traditional proof sets and mint sets while the country faced a nationwide coin shortage.
Understanding what SMS coins are—and how they differ from proof or regular circulation coins—can help collectors identify them and appreciate their place in U.S. numismatic history.
Why Special Mint Sets Were Created
In the early 1960s, the United States experienced a severe coin shortage. Several factors contributed to the problem:
Rising silver prices
Hoarding of silver coins by the public
Increasing demand for coinage in a growing economy
At the same time, the government passed the Coinage Act of 1965, which eliminated silver from circulating dimes and quarters and reduced the silver content of half dollars.
To simplify coin production and discourage collectors from hoarding coins directly from circulation, the U.S. Mint made several major changes:
Mintmarks were temporarily removed from coins
Traditional proof sets were suspended
Standard mint sets were discontinued
Instead, collectors were offered Special Mint Sets.
What Coins Are Included in an SMS?
Each Special Mint Set contained one example of every circulating U.S. coin struck that year:
Cent
Nickel
Dime
Quarter
Half Dollar
All of these coins were produced without mintmarks during the 1965–1967 period.
How SMS Coins Were Made
SMS coins were struck with greater care than normal circulation coins but not to the same standards as proof coins.
They typically feature:
Sharper strikes than circulation coins
Cleaner surfaces
Satin or semi-reflective finishes
However, they lack the highly polished mirror fields and frosted devices commonly seen on modern proof coins.
Because of this, SMS coins often appear somewhere between circulation strikes and proofs in overall quality.
Special Mint Sets vs Proof Sets
Collectors sometimes confuse SMS coins with proof coins. While they may look similar at first glance, there are important differences.
FeatureSpecial Mint SetsProof CoinsFinishSatin or semi-reflectiveMirror-like fieldsStrike qualityHigher than circulationExtremely sharpProduction years1965–1967Most other yearsMinting purposeTemporary replacementCollector-focused
Proof sets returned in 1968, produced at the San Francisco Mint.
Are SMS Coins Valuable?
Most Special Mint Sets are affordable and widely available today. Millions were produced each year:
1965 SMS: about 2.36 million sets
1966 SMS: about 2.26 million sets
1967 SMS: about 1.86 million sets
Because of these relatively high mintages, standard SMS coins typically carry modest collector premiums.
However, certain coins can be more valuable if they feature:
Exceptional strike quality
Deep cameo contrast
High grading scores from certification services
Some SMS coins with strong cameo effects can command significantly higher prices among collectors.
The Mystery of the 1964 SMS Coins
One intriguing footnote in this story involves rumored 1964 Special Mint Sets.
A very small number of coins with SMS-like finishes dated 1964 have surfaced over the years. These coins appear to have been experimental strikes produced before the official SMS program began.
Only a handful are known, making them extremely rare and highly valuable among advanced collectors.
Why Collectors Like SMS Sets
Special Mint Sets remain popular among collectors for several reasons:
They represent a unique period in U.S. coin history
They are relatively affordable
They include attractive coins with above-average strikes
For many collectors building modern type sets, SMS coins are an interesting addition that bridges the gap between circulation coins and proofs.
Final Thoughts
Special Mint Sets were created during a turbulent time in U.S. coinage history when rising silver prices and coin shortages forced the government to rethink how coins were produced and distributed.
Although they were only issued from 1965 to 1967, SMS coins remain a fascinating reminder of this transitional period. For collectors interested in modern U.S. coinage, they offer an affordable and historically meaningful set to add to a collection.