Generally service parts planning differs from final product planning in the following ways:

1. A high number of low volume irregular demand items in the planning database
2. Inapplicability of traditional measures of forecast error (service parts management has much higher month by month forecast error than finished good forecasting. A service part can go many months with no demand at a product/location)
3. A higher necessity to manage many locations as a single inventory “pool” – this means more transshipments between various inventory holding locations
4. More complexity in procurement (end of life, lifetime buy, phased out suppliers) leading to different inventory holding strategies
5. High variability in repair lead times (due to un-serviceable items which require inspection prior to repair lead time estimation)
6. Inapplicability of common high volume forecasting and inventory management techniques (such as high volume forecasting algorithms and EOQ or POQ)
7. Higher emphasis and need to handle obsolescence supersession and substitutability.