Lists
The official Army List was published at least annually from 1740 and records all officers. Hart's Army List was published from 1839 to 1915 and supplies more information about individuals' army careers. Both publications are available at the National Archives. Annotated copies, sometimes including supplemental details are in the reference series (PRO) WO65 (1754-1879) and (PRO) WO66 (1879-1900).

Commissions
Records concerning the purchase and sale of the commissions of Irish officers from 1768 to 1871 can be found in PRO reference series (PRO) HO123. Correspondence relating to commissions generally between 1793 and 1871 is in (PRO) WO31. The records are arranged chronologically, can be extremely informative and are relatively simple to use, since the date of commission is supplied by the Army List.

Service Records
These records, in The National Archives reference series (PRO) WO25, are not comprehensive, consisting of a series of surveys carried out every 15 to 20 years between 1809 and 1872. The early returns concentrate on military service, with some biographical detail supplied in the later ones. The records are covered by an alphabetical card index on open access, which also takes in reference series (PRO) WO75, an episodic series of regimental service returns between 1755 and 1954.

Pensions
Up to 1871, if an officer did not sell his commissions on retirement he went on half-pay, a retainer that meant he was theoretically available for service. Records of these payments, as well as widows' and dependants' pensions, can provide detailed biographical information. The half-pay ledgers of payment from 1737 to 1921 are in The National Archives record series (PRO) PMG4, arranged by regiment up to 1841 and thereafter alphabetically. The record series (PRO) WO25 also contains much detail on pensions and dependants.

Other
Many officers' original baptismal certificates are included in War Office records, for 1777-1868 in record series (PRO) WO32/8903 to (PRO) WO32/8920 (code 21A) and for 1755 to 1908 in (PRO) WO42. Both are indexed.