The cost per foot of fiber optic cable is now the lowest it's been since 2021. Labor dominates the installed price. Total Project Costs: For commercial installations, expect costs ranging from $5,000 to $20,000 per mile for underground projects and from $40,000 to $60,000 per. Anyone with experience in the field would first answer, “It depends,” listing factors affecting expenditures that include labor, underground vs. Assumptions: region, fiber type, trench method, and crew size; estimates reflect typical. The median cost of labor and materials to deploy underground fiber is $18. These cables include gel-filled cores and water-blocking protection. HDPE conduits last longer than PVC but cost slightly more upfront.