The following is the Bulgarian order of battle at the beginning of the First Balkan War as of October 8, 1912. After its mobilization the field army counted for 366,209 men^[1] and represented half the field forces of the Balkan League. Its greater part was deployed in the main theater of the war in Thrace^[2] but the army also contributed to the allied war effort in Macedonia. This order of battle includes all combat units, including engineer and artillery units, but not medical, supply, signal and border guard units.

The nominal commander in chief of the Bulgarian Army was Tsar Ferdinand I but de facto its control and leadership were in the hands of his deputy Lieutenant-General Mihail Savov. The Chief of the General Staff was Major-General Ivan Fichev with Colonel Stefan Nerezov as his Deputy Chief.

The basic Bulgarian infantry division consisted of three infantry brigades, each of two infantry regiments, with each regiment containing four infantry battalions.^[3] Additionally these divisions contained two artillery regiments, a cavalry regiment and an engineer battalion. Their full battle strength consisted of 24 infantry battalions while their total strength made them the equivalent of an army corps.^[4] Due to tactical necessities the 1st and 6th divisions each gave one brigade for the formation of a new 10th division and fought during the war with a battle strength of 16 battalions.