Gear ratio reference

2025 Mercury 250 HP SeaPro Gear Ratio

Exact Model / Lower Unit Ratio

Listed gear-ratio data for 2025 Mercury 250 HP SeaPro outboards. Match your exact model and lower unit; some models may have more than one gearcase configuration.

2025 Mercury 250 HP SeaPro

Listed ratio values: 1.85:1

Model Gear ratio
CURRENT 1.85:1

Use the ratio that matches your exact outboard model and lower unit, then enter it in the PropSlip calculator.