The entire mintage of 1966 nickels was produced during the final five months of that year, as the earlier months had been devoted to back-dated 1964 and 1965 coins. Though this issue carries no mintmark, all 1966 nickels were coined at Denver (103,546,700) and San Francisco (52,661,583).
Gems of this issue are not especially rare, and satisfactory coins may be found. Precious few, however, will display 5FS, while 6FS coins are extremely rare.
The Special Mint Set issues for collectors were struck at San Francisco, and the 1966 editions are more uniformly brilliant than those dated 1965.
Gems are plentiful, though the frequent lack of full striking on the highest points left areas of rough and nicked planchet marks. Thus, the percentage of top-graded pieces is lower than for true proofs. Cameo and Ultra Cameo coins are available but are likewise less common than for proofs of the early 1960s.
Mintage:
| Philadelphia | Special Mint Set |
| 156,208,283 | 2,261,583 |