The regiment briefly served dismounted as infantry in the defenses of New Orleans, June–September, 1864.

The regiment was attached to Defenses of New Orleans, Department of the Gulf, to March 1864.

The 3rd Rhode Island Cavalry mustered out of service November 29, 1865.

1st Battalion moved to New Orleans, La., December 31, 1863, to January 14, 1864 aboard the steamer Western Metropolis.

Reached Fort Banks, opposite New Orleans, June 2.

Companies G and H reported at New Orleans May 8 and joined the regiment at Greenville June 10.

Regiment dismounted June 22, and served duty as infantry in the defenses of New Orleans until September.

Assigned to duty in the District of LaFourche at Donaldsonville, Napoleonville, Thibodeaux, Camp Parapet, Plaquemine, Houma, Hermitage Plantation, and other points in Louisiana, scouting and patrol duty and operating against guerrillas, until November 1865.

Expedition from Brashear City to Whiskey Bayou January 16–18, 1865 (Companies B, I, and K).

Expedition from Thibodeaux to Lake Verret and Bayou Planton January 30–31 (Company H).

Expedition from Terre Bonne to Pelion's Plantation and Grand Caillou April 19–25 (Company M).