This table was originally based on an older blog entry by Ronald D. Moore posted in 2005, in which he replies to a question about the show's rank structure (see Official Statements below). It has been expanded and altered since that time to include additional ranks that have been established since then (lieutenant colonel, rear admiral) and heavily supplemented by sources close to the show as well as a recently released rank pin chart. It should be noted that some of the ranks on the pin chart are listed differently elsewhere on this page for practical reasons. In some cases this is done because the rank given on the pin chart is assumed to represent a position rather than a specific rank (i.e. the only reference to term senior chief on screen (in "Blood on the Scales") appears to use it as a position rather than a rank, since only Tyrol holds the position of senior chief but both he and Peter Laird are chief petty officers) or because the the rank on the pin chart is consistently referred to differently on screen (i.e. crew specialist has always been referred to as specialist).
The ranks are a mix of naval and marine ranks inherited from the Original Series, but mirror naval practices in execution and are elaborated during the series both on-screen and in production notes. It is possible to create a rough equivalence to real world armed forces. However, while the Colonial Fleet has many parallels with modern armed forces it is a fictional organization and diverges from reality in certain places, for example in the duties of commanders and admirals, or the place of the CAG within the ship's hierarchy.
The officer ranks of the Colonial Marine Corps (CMC) have yet to be established on screen (with the exception of lieutenant) or by official sources and thus are not listed here. The Marine Corps's enlisted ranks largely mirror real world ranks. 
These pictures were created by Jim Stevenson a.k.a. "137th Gebirg". With more recent device created by members of the battle star wiki community using his original designs as templates.
Senior officers' ranks can also be identified by the color of the piping on their uniforms. The rank for lieutenant colonel is depicted as worn by Jack Fisk in "Razor", although the same insignia has also been worn by others with the simple junior officer white piping.
As mentioned above some of these ranks differ from that listed elsewhere on Battlestar Wiki for practicality purposes. In addition it is important to remember that each enlisted device corresponds to two ranks: the colonial fleet version and its colonial marine corps rank equivalent.
- In a blog entry on February 19, 2005 Ronald Moore gave a little insight into the rank structure of Battlestar Galactica:
"What is the rank structure? It doesn't seem consistant [sic] with the Navy."
The rank structure is derived from the original series. I didn't want to change Commander Adama to Captain Adama or Colonel Tigh to Commander Tigh, so I elected to simply embrace the co-mingled nature of the original rank structure. For our internal purposes, we've decided that the ranks are indeed a mixture of naval and army nomenclature and are basically as follows:
- Lieutenant Junior Grade
- Master Chief Petty Officer
- Chief Petty Officer
- Petty Officer (1st, 2nd Class)
- Deck Hand
Just to complicate matters further, there are also Marines aboard Galactica which conform more closely to the traditional enlisted Marine ranks, with Sergeants, Sergeant-Majors (sic), etc. Unresolved is the question of whether the Marine officers would also adhere to the mixed rank structure (which sounds odd) or if they are strictly army equivalents (which makes no sense given that the "Navy" ranks seem oblivious to there being any such distinction). Aren't you glad you asked?
- Uniforms (RDM) - Uniforms of the Re-imagined Series.
- Insignia (RDM) - Additional insignia and patches for uniforms in the Re-Imagined Series.
- Military Ranks (TOS) - Ranks of the Original Series.
A detailed analysis of Battlestar Galactica's uniform devices by Jim Stevenson. Also the source for this article's images.
- Sergeant First Class:
- Unlike the other CMC enlisted ranks, this is not a US Marine Corps rank but the US Army equivalent to gunnery sergeant.
- In "Litmus" Sergeant Hadrian wears insignia listed here as petty officer 1st class. The term sergeant first class is never used on screen. However, behind the scenes documents list the Marine rank associated with the single chevron on green background worn by Hadrian (and shared with the rank of petty officer first class) as sergeant first class.
- Admiral: Peter Corman wears the same admiral insignia as Adama and Cain, but with thick gold piping on his duty uniform. This raises the question of how a rear admiral can be distinguished from a full admiral in dress uniform, given that dress uniforms have no colored piping. It can be speculated that, as has been the case with the ranks of ensign and junior lieutenant, the production crew uses the same insignia for both admiral ranks, as only one type of admiral pin has been made for the show. It would normally be expected that different admiral grades would be distinguished by the number of gold bars (for example one set for a rear admiral, etc).
- Rear Admiral:
- In the extended version of the episode "Pegasus", Adama states "Fleet promoted her to rear admiral over half of the commanders on the list.", thus establishing this rank.
- When Adama is promoted to admiral in "Resurrection Ship, Part II" his new rank insignia are identical to Cain's.
- Cain seems to command both her battlestar and its Battlestar Group. In modern practice, a captain (the real-world rank most similar to the colonial rank of commander) commands only the ship, while an admiral is in charge of the Carrier Strike Group and is often on the same ship as a captain.
- While Cain wears a regular rear admiral's duty uniform with gold-over-silver piping, Adama continues to wear his commander's duty uniform with red-over-gold piping after his promotion to admiral. From a production point of view, this was most likely done so that the crew didn't have to create a new set of uniforms for the actor, but can be explained in-universe by a lack of male admiral uniforms in the Fleet's stores following the attack on the Twelve Colonies. Similarly, Hoshi also wears his lieutenant's duty uniform with one line of solid white pipping after his promotion to admiral.
- Lieutenant Colonel:
- This information comes from production materials, which note Jack Fisk's rank as lieutenant colonel in the portions of "Razor" before Jurgen Belzen is executed. Fisk wears different rank insignia from the normal colonel insignia, as seen here and here.
- These devices have been previously used for Dualla in "Lay Down Your Burdens, Part II", but she is identified as a lieutenant in dialog. Insiders have indicated that Dualla's use of the lieutenant colonel insignia was a costuming error/necessity, that was necessitated during her first appearances after becoming an officer because there weren't enough junior lieutenant devices to go around. It has also been noticed that other characters including Chief Tyrol have used them from time to time for the same reason.
- Fisk's uniform piping as a lieutenant colonel is the same red-over-white as on a full colonel's uniform. Given that he is the only person ever even referred to as holding that rank, it is likely safe to assume that lieutenant colonel and colonel share the same colors. This is unusual in that all other senior officers' uniforms have distinctive piping, but can be explained by their potentially similar duties. However, this may - like the use of some rank devices - be a production necessity: It was far easier to use the actor's existing uniform than create a new one (Fisk's first appearance took place within the show's timeline after he had already been promoted to full colonel as Razor was filmed in between that season and the following one.
- After her promotion to major in "Razor", Shaw wears a colonel's red-over-white piping instead of the normal simple white piping normally worn by all junior officer ranks. This may have been an intentional decision to denote her position as Pegasus's XO, or just a costuming error.
- Agathon states his rank as "lieutenant junior grade" in "33", but he consistently wears the rank insignia of a full lieutenant.
- Junior Lieutenant:
- The term "junior lieutenant" (or JRLT in short) is used in props and behind the scenes documentation. For example on Boomer's Raptor nameplate in the Miniseries and Kara Thrace's disciplinary records in "The Son Also Rises". Although "lieutenant, junior grade" has also been used in dialogue a few times, for example by Karl Agathon in "33", the vast majority of on-screen references and behind-the-scenes documentation use the term "junior lieutenant", and is thus the term preferred by Battlestar Wiki.
- While Ron Moore's blog entry from a couple seasons ago (see "Official Statements" below) uses the term "lieutenant junior grade," it should also be pointed out that other differences between the blog entry and the actual terminology and structure have been definitively proven since that entry was written.
- Warrant officer: Although to-date it has not been referenced in spoken dialogue, the rank of warrant officer is included in costuming notes, and is worn on-screen by background extras. It's existance is further supported by the uses of white uniforms by many background extras which are unique from the standard enlisted and commissioned officer uniforms.
- Specialist: The end credits for "Flight of the Phoenix" and "Revelations" list Anthony Figurski as specialist, 3rd class. Furthermore the rank of specialist, 2nd class was mentioned by writer Bradley Thompson in the Official Communiques. This indicates that there are three subdivisions for this rank which are used in the scripts. However, these ranks have not been used in dialogue yet and only a single rank insignia for specialists has been established so far.
- Lance Corporal: The rank of lance corporal is introduced in "The Oath" with Eduardo Maldonado, however, no insignia is ever shown, and the new pin chart doesn't seem to have a separate rank device for it, it's unclear whether this is a mistake on the part of the writing staff or whether it is intended to be a separate rank.
- Crewman: Many sources, including Ron Moore's blog, refer to this rank as "deckhand." However, more recent internal documents reveal the rank to be "crewman."
- Junior Lieutenant/Ensign Rank Device: The use of junior lieutenant insignia for the rank of ensign in episodes like "Scar" and "Dirty Hands" is a costuming necessity, as the production staff never created a separate pin for the ensign rank.
- Master Chief/Sergeant Major Rank Device: The rank device for master chief petty officer/sergeant major has never been worn on-screen as such, but the design is part of the civilian flight wings worn by the pilot of Colonial One.
- Crewman Apprentice/Private: These insignia have not yet been shown on-screen, but are found in production materials.