Here is the full list of active-duty military units deployed to the southern border.
article March 1, 2019
https://taskandpurpose.com/border-deployment
AIR FORCE
819th Red Horse Squadron
ARMY
36th Engineer Brigade
5th Engineer Battalion
563rd Military Police Company
595th Engineer Company
161st Engineer Support Company
Alpha Company, 52nd Engineer Battalion
Alpha Company, 16th Engineer Battalion
Forward Support Company, 5th Engineer Battalion
1st Support Maintenance Company
542nd Support Maintenance Company
584th Support Maintenance Company
46th Engineer BattalionForward Support Company, 46th Engineer Battalion
108th Military Police Company
515th Engineer Company
610th Engineer Support Company
147th Support Maintenance Company
602nd Support Maintenance Company
503rd Military Police Battalion
66th Military Police Company
41st Engineer Company
4th Sustainment Brigade
264th Combat Sustainment Support Battalion
227th Quartermaster Company
178th Adjutant General Company
126th Transportation Company
155th Transportation Company
377th Transportation Company
259th Movement Control Team
153rd Quartermaster Company
1st Squadron, 14th Cavalry Regiment
Alpha Company, 1st Squadron, 14th Cavalry Regiment
Bravo Company, 1st Squadron, 14th Cavalry Regiment
Charlie Company, 1st Squadron, 14th Cavalry Regiment
1st Battalion, 37th Field Artillery Regiment
Headquarters and Headquarters Battery, 1st Battalion, 37th Field Artillery Regiment
Charlie Company, 1st Battalion, 37th Field Artillery Regiment
Charlie Company, 1st Battalion, 23rd Infantry Battalion
3rd Combat Aviation Brigade
4th Battalion, 3rd Combat Aviation Brigade
24th Theater Public Affairs Support Element
63rd Expeditionary Signal Battalion
505th Military Intelligence Brigade
MARINE CORPS
7th Engineer Support Battalion
Alpha Company, 1st Law Enforcement Battalion
Alpha Company, 2nd Battalion, 5th Marine Regiment
Bravo Company, 2nd Battalion, 5th Marine Regiment
CE Company, 7th Engineer Support Battalion
Combat Logistics Battalion 5
1st Light Armored Reconnaissance Battalion
Echo Company, 2nd Battalion, 4th Marine Regiment
Golf Company, 2nd Battalion, 4th Marine Regiment