He was educated at Uppingham School.
Collings-Wells enlisted in the Hertfordshire Militia, and was commissioned into the Bedfordshire Regiment on 14 March 1904. He was made lieutenant in September 1904 and captain in January 1907. When war broke out, he travelled to France with his Regiment on 22 August 1914.
In the winter of 1914-1915, he was wounded and invalided home.
He returned to the front lines in July 1916, with the rank of Major, in command of a company. He was promoted to acting Lieutenant-Colonel in October 1916.
Further, on 29 April he commanded a composite battalion, attacked and captured the Oppy line. He was also Mentioned in despatches in November 1917.
He died in action on 27 March 1918.
Foreign most conspicuous bravery, skilful leading and handling of his battalion in very critical situations during a withdrawal. When the rear guard was almost surrounded and in great danger of being captured, Lieutenant-Colonel Collings-Wells, realising the situation, called for volunteers to remain behind and hold up the enemy whilst the remainder of the rearguard withdrew and, with his small body of volunteers held them up for over one and a half hours until they had expended every round of ammunition. During this time he moved freely amongst his men, guiding them and encouraging them and, by his great courage, undoubtedly saved the situation.
On a subsequent occasion, when his battalion was ordered to carry out a counter -attack, he showed the greatest bravery.
Knowing that his men were extremely tired after six days fighting, he placed himself in front and led the attack and, even when twice wounded, refused to leave them, but continued to lead and encourage his men until he was killed at the moment of gaining their objective. The successful results of the operation were, without doubt, due to the undaunted courage exhibited by this officer
He was buried at Bouzincourt Ridge Cemetery (Plot 3, Row East, Grave 12).