When the boy turned 6 years, his father, a Privy Counsellor and Senator, had him enrolled in the Preobrazhensky Regiment though it was not until November 1781 that he entered the Page Corps, matriculating in 1787 with the rank of Kammer-page.

On 21 January 1800 Balashov was dismissed from the military service, but in November of the same year he was appointed governor general and chief of garrisons regiment in Tallinn.

In November 1807 he became the general-krigs-komissar, on 29 March 1808 he replaced Fyodor Ertell in the office of chief of police in Saint Petersburg and thereupon his career soared.

After La Grande Armée crossed the frontier on June 12 (Julian Calendar), Balashov was dispatched to deliver the Emperor's letter to Napoleon.

He participated in the organization of the People's Militia (Народное ополчение) and was a member of the extraordinary committee choosing the commander-in-chief of the Russian army.