Exposition Station and advertising cancellations

According to William J. Bomar, the U.S. Government Post Office was located in sections N and O, Aisle 4 in the Commerce and Industries Building. The following is adapted from Bomar's book "Postal Markings of United States Expositions", Copyright ©1986:

• SD15-01 Steel-die duplex handstamp reads "San Diego, Cal. Exposition Sta." in circle - oval killer with numeral "1", year "1915" between - the only known exposition station cancellation for 1915
• SD16-01 same as above except used in 1916 - scarce
• SD16-02 double circle, reads "San Diego (Exposition Sta.) Cal. / Registered" in outer circle - an example on an official business envelope is known dated July 26, 1915
• SD16-03 double circle, reads "San Diego (Exposition Sta.) Cal. / MOB" in outer circle - 1916 - seen only as a proof strike on facing slip
• SD16-04 double circle, reads "San Diego (Exposition Sta.) Cal. / Parcel Post" in outer circle - 1916 - seen only as a proof strike on facing slip

Advertising cancels not made on Exposition grounds: American machines

• SD16-05 Pomona, Cal.   EKU=3/1916   LKU=12/30/1916
• SD16-06 Santa Monica, Cal.   EKU=3/30/1916   LKU=1/8/1917

Advertising cancels not made on Exposition grounds: Columbia Machines

• SD16-07 Long Beach, Cal.   EKU=3/13/1916   LKU=9/25/1916
• SD16-08 Redlands, Cal.   EKU=5/27/1916   LKU=9/15/1916
• SD16-09 Riverside, Cal.   EKU=5/5/1916   LKU=12/18/1916
• SD16-10 San Bernardino, Cal.   EKU=3/29/1916   LKU=4/22/1916
• SD16-11 Santa Barbara, Cal.   EKU=4/5/1916   LKU=1/3/1917
• SD16-12 Santa Rosa, Cal.   EKU=4/7/1916   LKU=7/4/1916

Advertising cancels not made on Exposition grounds: International Machines

• SD16-13 Alameda, Cal.   EKU=4/19/1916   LKU=12/23/1916
• SD16-14a Los Angeles, Cal.   Die space #1   March-June, 1916
• SD16-14b Los Angeles, Cal.   Die space #2   EKU=1/29/1916   LKU=12/31/1916
• SD16-14c Los Angeles, Cal.   Die space #3   EKU=10/31/1916   LKU=12/26/1916
• SD16-15a Los Angeles, Cal. Sta. C.   Die space #1   March-April, 1916
• SD16-15b Los Angeles, Cal. Sta. C.   Die space #2   August, 1916
• SD16-15c Los Angeles, Cal. Sta. C.   Die space #3   EKU=2/29/1916   LKU=5/13/1916
• SD16-15d Los Angeles, Cal. Sta. C.   Die space #4   EKU=4/19/1916   LKU=12/22/1916
• SD16-16 Oakland, Cal.   EKU=3/16/1916   LKU=1/10/1917
• SD16-17a San Francisco, Cal. Die space #1   April, 1916
• SD16-17b San Francisco, Cal. Die space #2   EKU=3/31/1916   LKU=12/31/1916
• SD16-17c San Francisco, Cal. Die space #3   EKU=2/25/1916   LKU=12/30/1916
• SD16-17d San Francisco, Cal. Die space #4   EKU=5/11/1916   LKU=12/23/1916

Advertising cancels not made on Exposition grounds: Universal Machines

• SD16-18 Bakersfield, Cal.   EKU=7/11/1916   LKU=12/19/1916
• SD16-19 Berkeley, Cal.   EKU=3/7/1916   LKU=12/20/1916
• SD16-20 Fresno, Cal. (wide spacing "Fresno")   EKU=4/7/1916   LKU=12/24/1916
• SD16-20a Fresno, Cal. (narrow spacing "Fresno")   EKU=4/7/1916   LKU=12/24/1916
• SD16-21 Pasadena, Cal.   EKU=3/13/1916   LKU=12/27/1916
• SD16-22 Sacramento, Cal.   EKU=3/27/1916   LKU=12/29/1916
• SD16-23 San Diego, Cal. ("Panama-California / Exposition / San Diego---1915" slogan in wavy box)   EKU=12/16/1914   LKU=12/26/1915
• SD16-24 San Diego, Cal. ("Panama-California / International Exposition / at San Diego-1916" slogan in wavy box)   EKU=3/20/1916 LKU=12/7/1916
• SD16-25 San Diego, Cal. ("Panama-California / Exposition / San Diego----1915" slogan in rectangle)   EKU=10/20/1913   LKU=11/23/1914
• SD16-26 Stockton, Cal.   EKU=5/21/1916   LKU=12/21/1916

EKU=earliest known use
LKU=last known use