How to Identify Precanceled Envelopes

Type of Printing

1 - Large serifed capital letters
2 - Small serifed capital letters
3 - Small san-serifed capital letters

State Name Designation

a - Abbreviated state name
b - Unabbreviated state name

Code number used for the Proper P.L & R. phrase

1 - (Sec. 435 1/2 P.L. & R.)	5 - (39 C.F.R., 34.65(e)
2 - (Sec. 562 P.L. & R.)	6 - (39 C.F.R., 34.66)
3 - (Sec. 34.66 P.L. & R.)	7 - (Non-Profit Organization)
4 - (Sec. 34.65(3) P.L. & R.)	8 - (Bulk Rate)

With the above identified, you will end up with a number, letter, number combination, i.e. 1a1, 1b2, 1b2, 3a3, 3a7, etc.  Here are some examples:

Type 1a1	Type 1a2
Type 2a1	Type 2a2
Type 3a2	Type 3a3
Type 3a4	Type 3a5
Type 3a6	Type 3a7
Type 3a8

Die	Description	Example
A	1 cent, Circular Die A of 1916-50.  Round "C" of "CENT"
E	1 cent, Circular Die C of 1916-50.  Rectangular "C" of "CENT"
O	1 cent, Green Oval die of 1950
X	1 1/2 cent, Brown Oval die of 1950
1A	1 1/4 cent, Die A, Turquoise Oval die of 1960. Thin left leaves.
1B	1 1/4 cent, Die B, Turquoise Oval die of 1960. Fat left leaves.
2C	2 cent, Die C, Red Oval of 1950	Sorry, No Picture.  Similar to 2D.
2D	2 cent, Die D, Red Oval of 1950
2+	2 1/2, cent Blue Oval of 1960

 

Envelope Size:

Government issued precanceled envelopes only came in 4 sizes:

Size 5	89 mm x 160 mm
Size 6 3/4	92 mm x 165 mm
Size 8 (10)	105 mm x 241 mm
Size 13	98 mm x 171 mm

Envelope Color:

Until December 12, 1943 precanceled envelopes where made in 3 colors: White, Amber, and Blue.  After that date, all were White.

Window Envelopes:

Precanceled envelopes have been issued with a glassine window in the face, so that an address printed on the enclosure can be read through the window.  These envelopes were typically un-gummed and low-back types.  After December 31, 1949, window precanceled envelopes were discontinued.

Envelope Gum and Knife:

The earliest government precanceled envelopes were issued with a gummed flap.  Beginning in January 1930 all were issued un-gummed.  The knife refers to how the envelope was cut in it's manufacture.  For precanceled envelopes only two varieties exist: high-back and low-back.  

High-back: the underfold of the envelope extends nearly to the top of the back of the envelope.

Low-back: the underfold extends but little more than half way up the back of the envelope.

Using all of the above characteristics, collectors have put together a system to describe each envelope.  This code is used instead of the more widely known Thorp system, since precanceled envelope collectors began collecting them without knowledge of the Thorp system.    The system first devised by D.D. Berolzheimer is shown below:

Size 5 (89 mm x 160 mm)

No.	Color	With Gum		No.	Color	No Gum		No.	Color	Window, No Gum
1	White	Low Back		7	White	Low Back		13	White	Low Back
2	Amber	Low Back		8	Amber	Low Back		14	Amber	Low Back
3	Blue	Low Back		9	Blue	Low Back		15	Blue	Low Back
4	White	High Back		10	White	High Back		16	White	High Back
5	Amber	High Back		11	Amber	High Back		17	Amber	High Back
6	Blue	High Back		12	Blue	High Back		18	Blue	High Back

 

Size 8 (10) (105 mm x 241 mm)

No.	Color	With Gum		No.	Color	No Gum		No.	Color	Window, No Gum
21	White	Low Back		27	White	Low Back		33	White	Low Back
22	Amber	Low Back		28	Amber	Low Back		34	Amber	Low Back
23	Blue	Low Back		29	Blue	Low Back		35	Blue	Low Back
24	White	High Back		30	White	High Back		36	White	High Back
25	Amber	High Back		31	Amber	High Back		37	Amber	High Back
26	Blue	High Back		32	Blue	High Back		38	Blue	High Back

 

Size 13 (98 mm x 171 mm)

No.	Color	With Gum		No.	Color	No Gum		No.	Color	Window, No Gum
41	White	Low Back		47	White	Low Back		53	White	Low Back
42	Amber	Low Back		48	Amber	Low Back		54	Amber	Low Back
43	Blue	Low Back		49	Blue	Low Back		55	Blue	Low Back
44	White	High Back		50	White	High Back		56	White	High Back
45	Amber	High Back		51	Amber	High Back		57	Amber	High Back
46	Blue	High Back		52	Blue	High Back		58	Blue	High Back

 

Size 6 3/4 (92 mm x 165 mm)

No.	Color	No Gum
66	White	High Back