Vulcan ranks
The military forces of the Vulcan High Command maintained a rank structure roughly equivalent to that of the Starfleet. ()

Fleet commander
Fleet commanders reported directly to the High Command. They oversaw and commanded fleet engagements. ()

Captain

Captain was the rank commonly held by Vulcan starship commanders and other senior officers. () In the 1950s, Vulcan ship captains wore an angular-swirl insignia mirrored on the left and right collar, and additional dark striping from other officers on their uniform. ()

By 2151, Vulcan captains wore a single rank pin on their left collar. ()
 
 Captain Oratt
 Captain Sopek
 Captain Tavek
 Captain Tellus
 Captain Tok
 Captain Vanik
 Captain Voris

Sub-commander

Sub-commander was a rank subordinate to a Vulcan captain. In dealing with Starfleet, a sub-commander was considered above the rank of commander and below the rank of captain. ()
 Sub-Commander Muroc
 Sub-Commander T'Pol

Major

Major was a rank held by senior Vulcan field agents. ()
 Major Talok

Subaltern
Subaltern was a rank that existed sometime before 2375. ()
 Subaltern Lorot

Sublieutenant

Sublieutenants were junior officers of the High Command. A sublieutenant manned a security post outside Administrator V'Las' office. ()

Background information
The Vulcan rank system seems to have been similar to Romulan ranks, including the use of sub-commander and sublieutenant.

The ranks of commander and lieutenant have never been referenced on-screen.

 Vulcan ranks

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