Interpreting Church History Call Numbers

By Tyson Thorpe, reference coordinator
14 January 2020

Learn about library call numbers and what they can tell you about the items in the Church History Library Collection in this post by Tyson Thorpe.

A call number is an address for locating material within a library or archive. Understanding call numbers can help you quickly determine what an item is and decide whether it may be of use to you in your research.

For most published items, like books, magazines, or pamphlets, the Church History Library uses the standard Dewey decimal classification system or a modified version for books on topics relating to The Church of Jesus Christ of Latter-day Saints. For archival items, call numbers include two letters, indicating a material type, followed by numbers.

Dewey Decimal Classification System

The Church History Library uses the Dewey decimal classification system to give a call number to items that contain little or no information about the Church but are helpful in providing context to Church history and the lives of Latter-day Saints.

Items catalogued in this way may treat a wide variety of topics. You will find things in our collection ranging from Illustrated Review: Fifteenth Infantry, United States Army, Fort Douglas, Utah (356.1 R965f 1909), which offers a history and photographs of the regiment, to Utah Musical Journal (780.5 M987), a very short-lived magazine “devoted to music, art, literature and the drama” in Utah.

Mormon Classification System

Since most of the library’s collection deals with The Church of Jesus Christ of Latter-day Saints, we needed a more precise way to catalog the massive amounts of material that would normally be found in a very narrow section of the standard Dewey decimal classification system. The Mormon classification system was created in the 1970s by expanding the Dewey category for religion (200–299) and placing an M in front of all call numbers.

Some examples of items cataloged under the Mormon classification system are the long-running magazine Millennial Star (M205.5 M646 v. 1–132 1840–1970), Ben E. Rich’s Interview on Mormon Faith (M230 R498g 1904 no. 2), and many of the old Sunday School manuals (such as M257.36 S957gd 1976–1977).


These collections contain content in audio or video format such as vinyl records, videocassettes, or filmstrips. At the library, we catalog them in two different ways depending on whether the item is commercially produced or not.

For those that are commercially produced, the call number is simply a series of numbers assigned by our cataloging system. For items that are not commercially produced, we assign a call number beginning with AV and followed by a number, assigned sequentially. Our new catalog now provides a way for us to share AV materials online, and we have begun with some of our most significant collections, such as general conference video (AV 3500) and audio (AV 3501).

CR—Church Records

These collections are the records of the institutional Church, whether the whole or one of its parts, such as the Church History Department or the Primary organization. The call number begins with CR and is followed by two sets of numbers. The first set is the number assigned to the Church entity, and the second set is the record series.

For example, the call number for the Historical Department Office Journal is CR 100 1; 100 is the entity number assigned to the Church History Department (which is the current name of the Historical Department) and it is the first series of department records. The call number for the Journal History of the Church, which is found under CR 100 137, indicates that it was created by the department but much later than the office journal.

LR—Local Record

These are congregational records kept by members of Church units such as branches, wards, stakes, and missions. The call number begins with LR and is followed by two sets of numbers. The first set is the number assigned to each Church unit. The second set is for the specific series of record and shouldn’t be confused with the series used in corporate records as outlined above. You can read more specifics on these call numbers in my previous post “More on Local Records” and see some examples in the Manti Ward general minutes (LR 5253 11) and the Safotulafai Branch Relief Society minutes and records (LR 7727 14).


These collections predominantly contain materials such as journals, letters, and other paper materials and occasionally include photographs and audiovisual items. Some examples of manuscript collections are the Farmington City cemetery record (MS 26259), David Moore journal (MS 4625), and the Susa Young Gates papers (MS 7692).

OH—Oral History

Interviews conducted by Church History Department staff and volunteers are captured in audiovisual format. These collections occasionally contain transcripts, other documents, and photographs. The numbers are assigned sequentially as oral histories come into the library. A few of the oral histories held at the library are available online, such as an interview with Marion R. Bain Scott MacDonald Tacy (OH 903) and one with William S. Bradshaw (OH 300).


These collections contain photographic images, such as prints or negatives, and occasionally include paper materials or other media. These can be large collections such as the Kenneth R. Mays photographs (PH 9809) outlined in a previous post, or they can be single images such as a photograph of the Smith home in Harmony, Pennsylvania (PH 7).

WA—Web Archive

These are web-published materials, such as various pages of the Church website ( The Church News and Events archive (WA 116) is one example of our efforts to preserve internet records.

Worldwide Storage

The Church History Department operates several storage centers located around the world. Records located in these centers use a similar call number style that is specific to their location. The number begins with a two-letter code indicating their country location, followed by two numbers indicating which facility in the country. The last five digits of the call number, which are assigned sequentially, indicate the collection. For example, all records held at the Matthew Cowley Pacific Church History Centre in New Zealand begin their call number with NZ-01, indicating that the facility is located in New Zealand and that it is the first center in that country.

Matthew Cowley Pacific Church History Centre

Not all the materials in these facilities have been cataloged, so use Ask Us on our website to reach out and see what we can do about providing you access to a specific collection. (Please provide the call number in your request.)

Knowing more about the call numbers we use at the Church History Library will help you navigate our collections and find the most useful records needed for your research. You can also use the drop-down filter in the Church History Catalog to begin your searches with a call number. Just don’t forget to include spaces!