Per his military service record (regimental no. 4764), Thomas Delaney was born at Parramatta, N.S.W. He gave his age as 31 years and 1 month, his marital status as married, and his occupation as labourer. His description on his Certificate of Medical Examination was height 5 feet 3 inches tall, weight 119 lbs., with a medium complexion, blue eyes, and brown hair. His religious denomination was Church of England. He claimed that he had no previous military service.
His ‘Joined on’ date on his Attestation Paper was 11th November 1915 (the day the Coo-ees marched from Parramatta to Ashfield). He completed his medical examination and was attested at Ashfield on 11th November 1915.
After the Coo-ee March he went to Liverpool Camp as reinforcement for the 13th Battalion.
‘Tom Delaney’ was one of 14 ‘local boys’ (along with several other Coo-ees) to be presented with a sheepskin vest and a money belt, and a wristlet watch, at a farewell held in the Elite Hall in Guildford on Thursday 9th December 1915.
On his embarkation roll his address at time of enrolment was Woodville Road, Guildford, N.S.W., and his next of kin was listed as his wife, Mrs R. M. Delaney, at the same address.
On 8th March 1916 Private Delaney, along with many of the other Coo-ees, departed Sydney on the HMAT A15 Star of England, with the 15th reinforcements for the 13th Battalion.
He arrived in Egypt on 11th April 1916.
On 16th April 1916 he transferred to the 4th Pioneer Battalion at Tel El Kebir, Egypt.
On 4th June 1916 Private Delaney left Alexandria aboard the Transport Scotian bound for France. He arrived at Marseilles on 11th June 1916.
He served with the 4th Pioneer Battalion in France and Belgium.
On the 24th of January 1917 the 4th Pioneer Battalion was conducting works in the vicinity of Longueval, France when Private Delany was admitted to the 13th Australian Field Ambulance, then transferred to the ANZAC Corps Rest Station with Rheumatism. On 31st January 1917 he was transferred by Ambulance Train to the 2nd General Hospital where he was admitted on 1st February 1917, and diagnosed with Myalgia.
On 25th February 1917 Private Delaney was sent to the 4th Australian Division Base Depot at Etaples, France.
On 14th March 1917 he rejoined the 4th Pioneer Battalion when it was resting in the vicinity of Longueval, France.
On 23rd July 1917 Private Delaney was detached to the 2nd ANZAC Corps School.
Private Delaney rejoined the Battalion on 15th August 1917 when it was conducting works in the vicinity of Kemmel Hill, Belgium.
On 21st September 1918 Private Delaney was granted leave to England.
On 7th October 1918, whilst on leave, Private Delaney was admitted to the 1st Australian Dermatological Hospital at Bulford, England, sick. He was discharged from hospital to the Convalescent Training Depot at Parkhouse, England, on 11th November 1918.
Private Delaney marched into the No.1 Command Depot at Sutton Veny, England, on 26th November 1918.
On 15th January 1919 Private Delaney commenced his return to Australia aboard the HMAT City of Exeter.
He arrived in Australia on 6th March 1919. He was discharged Medically Unfit on 20th March 1919.
 NAA B2455, DELANEY T
 FAREWELLING. (1915, December 11). The Cumberland Argus and Fruitgrowers Advocate (Parramatta, NSW : 1888 – 1950), p. 5. Retrieved November 15, 2018, from http://nla.gov.au/nla.news-article86106306
 Australian War Memorial. First World War Embarkation Rolls, Thomas Delaney, HMAT Star of England A15, 8th March 1916.
 Australian Imperial Force unit war diaries, 1914-18 War, AWM AWM4 Subclass 14/16 – 4th Australian Pioneer Battalion, AWM4 14/16/11 – January 1917 ; NAA B2455, DELANEY T
 Australian Imperial Force unit war diaries, 1914-18 War, AWM AWM4 Subclass 14/16 – 4th Australian Pioneer Battalion AWM4 14/16/13 – March 1917
 Australian Imperial Force unit war diaries, 1914-18 War, AWM AWM4 Subclass 14/16 – 4th Australian Pioneer Battalion, AWM4 14/16/18 – August 1917