Have We Run Out of Unique 6 Character License Plates?

To determine if unique 6-character license plates have run out, we need to consider the possible combinations available with 6 characters. Assuming a license plate can consist of uppercase letters A-Z and digits 0-9, we have:

Character Options

This gives us a total of 36 possible characters for each position on the plate. For a 6-character license plate, the total number of unique combinations can be calculated as:

36^6 2,176,782,336

This means there are over 2 billion possible combinations of 6-character plates. Given this vast number, it is highly unlikely that any region has run out of unique 6-character license plates, unless they have very specific restrictions or formats that limit the available combinations significantly.

Examples and Specific Regions

However, some regions may have exhausted their supply or have specific formats that limit the combinations. For example, California provides an interesting case study. California long ago ran out of 3-letter 3-number combinations, impacting their license plate system.

California License Plate History

California started with the format ABC123, which yields 26^3 * 10^3 combinations, or approximately 11 million.

They ran out of these combinations around 1969. In response, they switched to the format 123ABC, which provided another 11 million combinations. These were predominantly on blue plates in the 1970s. Further iterations included 1ABC123, which provided around 11 million combinations for each digit in the sequence.

Currently, California is issuing plates in the 7XXX123 range and will likely start issuing 8000ABC within the next year. This translates to approximately 88 million plates with the 7 digits/letters and another 22 million for the others, making a total of over 100 million plates issued.

The speculation is that when they issue 9ZZZ999, they will start over with 1123ABC, but this remains uncertain.

For context, my plate 6BSTxxx was issued on my Saab in December 2007. If the 8-series reaches the B as the first letter in a year or so, it would take about 5-6 years to run through each first number. My wife's newer car has a 7Xxxxxx on it, issued in December 2016, indicating a continuous supply of new plates.

In Conclusion

In summary, while specific regions like California have encountered issues with non-unique license plates due to historical formats, the vast number of possible 6-character combinations (over 2 billion) means that most regions have not run out of unique plates. Jurisdictions can implement measures to recycle old plates or expand their formats to accommodate more combinations if necessary.

Keywords: unique license plates, license plate combinations, 6-character license plates