Back Scheduling
Definition
Back scheduling (backward scheduling) is a planning method that starts from a job's required due date and works backward through each operation's lead time to find the latest possible start date for every step.
In Practice
MRP systems use back scheduling to decide when to release a production or purchase order so the work finishes just in time for the demand date, minimizing how long inventory sits. For example, if an order is due on day 20 and its three operations take 3, 2, and 5 days, back scheduling places their start dates at days 15, 13, and 8.
It is the counterpart to forward scheduling, which starts from today and works forward. Planners lean on back scheduling when the priority is hitting a fixed customer date with the least early inventory and work-in-process.
Frequently Asked Questions
What is the difference between back scheduling and forward scheduling?
Back scheduling starts from the due date and works backward to find the latest safe start date, while forward scheduling starts from the current date and works forward to find the earliest finish. Back scheduling minimizes early inventory; forward scheduling shows the soonest a job can be completed.
When should a planner use back scheduling?
Use it when a job has a firm customer or shipment due date and you want to release it as late as safely possible to reduce work-in-process and holding cost. It is the default scheduling logic in most MRP-driven manufacturing environments.
What happens if back scheduling produces a start date in the past?
A start date in the past means the order cannot meet its due date with normal lead times. The planner must expedite by compressing setup or queue time, split the lot, offload work to another resource, or negotiate a new due date with the customer.
Related Calculators
Related Terms
Forward scheduling is a planning method that starts a job at the earliest available date — usually today — and adds each operation's lead time to project the earliest possible completion date.
Interoperation TimeInteroperation time is the elapsed time between the end of one operation and the start of the next on a manufacturing order, made up of queue, wait, move, and staging time rather than actual processing.
Time BucketA time bucket is the unit of time — typically a day, week, or month — into which a planning system groups demand, supply, and schedule data, defining the granularity of an MRP or forecasting plan.
Material Requirements Planning (MRP)Material Requirements Planning (MRP) is a calculation engine that translates a production schedule into time-phased requirements for every component and raw material, using bills of materials, inventory records, and lead times.