Call of Duty Black Ops 3
Saves | Game 100% Completed

Instructions on using COD Black Ops 3 save file:

2. Download desired Call Of Duty BO3 save file to your desktop and extract it.
3. Select all files within the extracted folder, right click and select Copy.
4. Navigate to game save location and paste copied files there.
5. Start your copy of Call Of Duty Black Ops III and your new save status will load automatically.

Game save location

Save folder for Call of Duty Black Ops 3 is different for each game version. Check these out:

C:\Program Files\Call of Duty Black Ops III\players

C:\Program Files (x86)\Activision\Call of Duty – Black Ops 3\players

C:\Users\\AppData\Local\VirtualStore\Program Files\Activision\Call of Duty - Black Ops 3\players\save

C:\Program Files (x86)\Steam\SteamApps\common\call of duty black ops 3\players\save

For brand new game installation:

If you have a brand new game installation (which means you didn't play game before using downloaded savegame), it is recommended to start the game, and exit right after the first mission starts.
Do it before following the instructions above. This method will create necessary files within the game save directory.