The 31-year-old joins a Salisbury side currently sitting second in the Southern League Premier South.
Ball will re-unite with former Farnborough midfielder Jaden Perez, as The Whites look to secure promotion to The Vanarama National League South.
Boro boss Spencer Day explained: “The loan suits all parties and gives Bally the opportunity to regularly play and have a real shot of another promotion.
“He can then come back Pre-Season refreshed and ready to go again for Boro. I’m certainly not ready to say a goodbye to Bally so hope it works out down there and he’s back in a Boro shirt in the summer.”
View the updated Squad list.