The 114th Illinois participated in the pursuit of the defeated Confederate army on 17–28 December 1864. After marching to Clifton, Tennessee, the regiment traveled on river transports to Eastport, Mississippi, where it was reassigned as XVI Corps pontoniers. The troops stayed in Eastport until 9 February 1865 when they were ordered to New Orleans, which they reached on 22 February. The unit boarded an ocean-going steamer at Lake Ponchartrain bound for the Mobile campaign. It reached the area on 23 March, after staging at Dauphin Island on 3 March. During the campaign, the 114th Illinois Pontoniers under Major Johnson were assigned directly to XVI Corps under A. J. Smith. The unit was present at the Battle of Spanish Fort which was evacuated by its Confederate garrison on the night of 8 April 1865. The regiment was ordered to attack Forts Tracy and Huger in pontoon boats but the Confederate garrisons already abandoned both positions. After Mobile surrendered, the unit marched to Montgomery, Alabama, reaching there on 24 April. The 114th Illinois spanned the Alabama River with a pontoon bridge and remained guarding it until 17 July, when the unit was ordered to Vicksburg.