How many miles from Jacksonville IL to Belleville IL?

124 miles. This is the best route:

1. Take I-72 EAST to I-55 SOUTH to St. Louis at EXIT 97A.
2. Take I-55 SOUTH to I-255 to Memphis and INTERSTATE 270. You want to follow signs to I-255 SOUTH towards MEMPHIS.
3. Take I-255 SOUTH to IL-15 EAST to BELLEVILLE at EXIT 17A.
4. Take IL-15 EAST to BELLEVILLE.