Block and Group Lists

The serial number ranges printed for each series and denomination are here broken down in three different ways: by blocks ("B"), complex blocks ("C"), and groups ("G"). For breakdowns of each series by date of production, see the monthly production tables.

Blocks

The block lists simply enumerate all the block-letter combinations used in the serial numbering of each series and denomination. Blocks printed for circulation are listed first, followed by blocks printed for the BEP's various special collector products.

Complex blocks

The lists of complex blocks are formatted much like the lists of simple blocks, but they distinguish different printings within a single block. In the more recent series, these splits typically occur when a block is printed partially at Washington (denoted by "dc") and partially at Fort Worth ("fw"); in many series from the '70s, the main distinction is between conventional and COPE overprinting ("cn" and "cp" respectively). In the 2009 $1's, COPE and LEPE overprinting are distinguished ("C" and "L"). Experimental and test printings are also considered to create new complex blocks; so far these include the web-press $1 notes in the early '90s ("web"), the Natick paper test notes in Series 1977A ("nat"), and the Gilbert paper test notes in Series 1963 ("gil"). The 1935G $1's without and with "In God We Trust" are also listed as separate complex blocks ("nm" and "mot" respectively).

Complex blocks which were printed for collector sales are denoted by a '$' in the lists, and those which were printed only for collector sales and not for circulation are further marked by a '+'. In a few cases where notes were printed but never issued for circulation, these have been marked by a '–'.

Groups

The group lists attempt to exhaustively catalog all the serial number ranges used for a given series and denomination. Of course, they fully break down all the Washington and Fort Worth ranges; but they also explicitly show the maximum serial numbers for each block, the star runs printed for notes (denoted 'n') vs. for sheets (denoted 's') or sometimes for both (denoted '&') (though there are some points at which I wonder about the accuracy of the n/s data), the many tiny gaps in the star note printings for some of the older series, and any other quirks that may have occurred. The general format is somewhat inspired by the old O'Donnell Handbook (which is an excellent source for detailed serialling information, but unfortunately has not had a new edition published since 1982), and is intentionally a bit minimalist, so as to be printer-friendly.

Where the uncut sheet printings are concerned, the BEP in recent years has not generally released precise serialling data. The serial ranges listed are therefore based on calculations from the serials of reported sheets, so some of them remain questionable pending further reports (see the survey of uncut sheets for more information); these are indicated by '?' in the lists.

It should be noted that the total count of groups given for each series is not necessarily equal to the number of lines in the list of groups. The count has been modified to more closely reflect the way collectors generally define a complete group set for a given series:

• A partial print run of star notes with gaps between positions (these were printed frequently between 1977 and 1995) is counted as one group, not 32. But for completeness (and for compatibility with O'Donnell), the result of counting each such run as 32 separate groups is also listed, as the total when "counting groups within runs".
• Similarly, when two classes of notes (generally web and non-web) are mixed within a single print run, the resulting run is counted as two groups, not 64.
• On the other hand, a single run of star notes which was printed as two sub-runs (as was often done between 1995 and 1999) is counted as two groups, not one. This is admittedly not terribly consistent, but again, seems to reflect the way the notes are commonly collected, and also the way the print runs are listed in the BEP's production reports.
• Another inconsistency in the star notes: Beginning with Series 1974 (in the $20's and below) and with the run-length change during Series 1977 (in the $50's and $100's), each print run of star notes is counted as a separate group, even if it is not separated by gaps from the surrounding runs; this reflects the fact that modern stars are often collected by print run. In earlier series, star groups are defined similarly to regular groups, since the smaller print runs and higher error rates of this era make the number of star runs printed unmanageably large for a collection.
• Finally, changes in the BEP's standard print run length have been indicated in the group lists, but in cases where different run lengths were used within a single block, they have not been considered as separate groups for purposes of the group count.