Regimental Correspondence is available for the following regiments of Indiana Volunteer Infantry troops, Cavalry, and Artillery units. Correspondence is also available for the 28th USCT (a federal regiment comprised mostly of African American Hoosiers).
| Roll # | Regiment | Notes |
| 01 | 06th IVI | |
| 02 | 07th IVI | |
| 03 | 08th IVI | |
| 04 | 09th IVI | |
| 05 | 10th IVI | |
| 06 | 11th IVI | spans 2 rolls |
| 07 | 11th IVI | spans 2 rolls |
| 08 | 12th IVI | |
| 09 | 13th IVI | |
| 10 | 14th IVI | |
| 11 | 15th IVI | |
| 12 | 16th IVI | |
| 13 | 17th IVI | |
| 14 | 18th IVI | |
| 15 | 19th IVI | |
| 16 | 20th IVI | spans 2 rolls |
| 17 | 20th IVI | spans 2 rolls |
| 18 | 21st IVI | 1st Indiana Heavy Artillery - spans 2 rolls |
| 19 | 21st IVI | 1st Indiana Heavy Artillery - spans 2 rolls |
| 20 | 22nd IVI | spans 2 rolls |
| 21 | 22nd IVI | spans 2 rolls |
| 22 | 23rd IVI | |
| 23 | 24th IVI | |
| 24 | 25th IVI | |
| 25 | 26th IVI | |
| 26 | 27th IVI | |
| 27 | 28th IVI | 1st Indiana Cavalry |
| 28 | 29th IVI | |
| 29 | 30th IVI | |
| 30 | 31st IVI | |
| 31 | 32nd IVI | |
| 32 | 33rd IVI | |
| 33 | 34th IVI | |
| 34 | 35th IVI | spans 2 rolls |
| 35 | 35th IVI | spans 2 rolls |
| 36 | 36th IVI | |
| 37 | 37th IVI | |
| 38 | 38th IVI | |
| 39 | 39th IVI | |
| 40 | 40th IVI | |
| 41 | 41st IVI | 2nd Indiana Cavalry |
| 42 | 42nd IVI | |
| 43 | 43rd IVI | |
| 44 | 44th IVI | |
| 45 | 45th IVI | 3rd Indiana Cavalry - spans 2 rolls |
| 46 | 45th IVI | 3rd Indiana Cavalry - spans 2 rolls |
| 47 | 46th IVI | |
| 48 | 47th IVI | |
| 49 | 48th IVI | |
| 50 | 49th IVI | |
| 51 | 50th IVI | |
| 52 | 51st IVI | |
| 53 | 52nd IVI | |
| 54 | 53rd IVI | |
| 55 | 54th IVI | |
| 56 | 55th IVI | |
| 57 | 56th IVI | |
| 58 | 57th IVI | |
| 59 | 58th IVI | |
| 60 | 59th IVI | |
| 61 | 60th IVI | |
| 62 | 61st IVI | |
| 63 | 62nd IVI | |
| 64 | 63rd IVI | spans 2 rolls |
| 65 | 63rd IVI | spans 2 rolls |
| 66 | 64th IVI | |
| 67 | 65th IVI | |
| 68 | 66th IVI | |
| 69 | 67th IVI | |
| 70 | 68th IVI | |
| 71 | 69th IVI | |
| 72 | 70th IVI | |
| 73 | 71st IVI | spans 2 rolls |
| 74 | 71st IVI | spans 2 rolls |
| 75 | 72nd IVI | |
| 76 | 73rd IVI | |
| 77 | 74th IVI | |
| 78 | 75th IVI | |
| 79 | 76th IVI | |
| 80 | 77th IVI | 4th Indiana Cavalry - spans 2 rolls |
| 81 | 77th IVI | 4th Indiana Cavalry - spans 2 rolls |
| 82 | 78th IVI | |
| 83 | 79th IVI | |
| 84 | 80th IVI | |
| 85 | 81st IVI | |
| 86 | 82nd IVI | |
| 87 | 83rd IVI | |
| 88 | 84th IVI | |
| 89 | 85th IVI | |
| 90 | 86th IVI | |
| 91 | 87th IVI | |
| 92 | 88th IVI | |
| 93 | 89th IVI | |
| 94 | 90th IVI | 5th Indiana Cavalry - spans 2 rolls |
| 95 | 90th IVI | 5th Indiana Cavalry - spans 2 rolls |
| 96 | 91st IVI | |
| 97 | 93rd IVI | |
| 98 | 92nd, 94th, 95th, 96th, 98th IVI | |
| 99 | 97th IVI | |
| 100 | 99th IVI | |
| 101 | 100th IVI | |
| 102 | 101st IVI | |
| 103 | 102nd through 114th IVI | Morgan’s Raid Regiments |
| 104 | 115th through 118th IVI | |
| 105 | 119th IVI | 7th Indiana Cavalry - spans 2 rolls |
| 106 | 119th IVI | 7th Indiana Cavalry - spans 2 rolls |
| 107 | 120th IVI | |
| 108 | 121st IVI | 9th Indiana Cavalry |
| 109 | 123rd IVI | |
| 110 | 124th IVI | |
| 111 | 125th IVI | 10th Cavalry |
| 112 | 126th IVI | 11th Cavalry |
| 113 | 127th IVI | 12th Cavalry |
| 114 | 128th IVI | |
| 115 | 129th IVI | |
| 116 | 130th IVI | |
| 117 | 131st IVI | 13th Cavalry |
| 118 | 132nd through 139th IVI | |
| 119 | 140th through 141st IVI | |
| 120 | 142nd IVI | |
| 121 | 143rd IVI | |
| 122 | 144th IVI | |
| 123 | 145th IVI | |
| 124 | 146th IVI | |
| 125 | 147th IVI | |
| 126 | 148th IVI | |
| 127 | 149th IVI | |
| 128 | 150th IVI | |
| 129 | 151st IVI | |
| 130 | 152nd IVI | |
| 131 | 153rd IVI | |
| 132 | 154th IVI | |
| 133 | 155th IVI | |
| 134 | 156th IVI | |
| 135 | 157th through 158th IVI | (158th) 2nd Artillery |
| 136 | 01st-04 th Battery | |
| 137 | 05th through 09th Battery | |
| 138 | 10th through 16th Battery | |
| 139 | 17th through 22nd Battery | |
| 140 | 22nd through 26th Battery | |
| 141 | 28th United States Colored Troops (USCT) |