| October 1939 | CO: Lt Col Sir Ronald Ross |
| Oct 39 | North Irish Horse |
| 1/10/39 | Belfast BOARD of OFFICERS held in County Hall ARMAGH consisting of CO, Lord Erne, Adjt to interview candidates for commissions. Further recce of GOSFORD CASTLE. |
| 3/10/39 | Two Sgts from 17/21st Lancers posted as PSIs. |
| 10/10/39 | Further recce of ENNISKILLEN. |
| 12/10/39 | CO admitted PURDYSBURN FEVER HOSPITAL, BELFAST suffering from Scarletina. Regtl strength in recruits is 29. |
| 15/10/39 | The following officers gazetted with effect from Sep 20th and granted acting rank of Captain:-
| CNL Stronge | The Lord O'Neill |
| RC Newton | AR Booth |
Lt MT McDonald arrived from 7th Btn RTC to assume duties of QM. |
| 17/10/39 | The following officers gazetted:- The Marquis of Ely, ADC Butler, JP Herdman. |
| 19/10/39 | 2Lt Marquis of Ely attached to 2nd Btn Royal Sussex Regt for signalling instruction. |
| 20/10/39 | The following officers gazetted:- CA Crofton, KG Pomeroy, RL Nugent, RJ Adams. 200 rifles and bayonets taken on charge. |
| 21/10/39 | Final recce of ENNISKILLEN by:-
| Col Holmes a'Court | Col i/c ADM NID |
| Col Findlay | CRE NID |
| Major Earl of Erne | |
results in decision to concentrate whole Regt there. The following officers attached to 2nd Btn SWB at LONDONDERRY for instruction in Regimental Duties:- Capts Stronge, Lord O'Neill, Newton, Booth, 2Lts Butler, Adams, Herdman, Crofton, Pomeroy, Nugent. |
| 23/10/39 | Lt MT McDonald MBE gazetted from 7th Btn RTC as QM |
| 31/10/39 | 27 recruits enlisted. Strength
| officers | 14 |
| WOs | 2 |
| ORs | 44 |
| Total | 60 |
|