The answer to "where is the Lightspeed reorder report?" depends on which Lightspeed Retail you run. On R-Series (the older Lightspeed Retail line), the classic reorder report still exists and is now called the Reorder list: go to Reports → Reorder list and you'll get every item below its reorder point with a Needed quantity you can turn into a purchase order. On X-Series (former Vend), there's no report named "reorder report" — you add Reorder Point and Reorder Amount columns to an inventory report, switch the measure to Low inventory, or use the Inventory replenishment report if you're on a Plus plan.
This guide covers both, step by step: setting reorder points, running the reports, turning them into purchase orders, and what the reorder math does and doesn't account for — from Lightspeed's own documentation.
R-Series: the Reorder list report
Set reorder points first. Go to Inventory → Item Search, open an item, and use the Reorder points page (cross-location view) or the item's Details page (per location). Two numbers per location: the reorder point (the level that triggers the flag) and the desired inventory level (what you want to get back up to).
The math. When quantity on hand drops to or below the reorder point, R-Series computes:
Need = desired level − (on hand + incoming on open POs + incoming transfers + stock in boxes)
So if your reorder point is 10, desired level is 20, and you have 5 on hand with nothing incoming, the report shows a Need of 15. Crediting Lightspeed here: counting inbound POs and transfers in the gap math is something plenty of "low stock report" features get wrong.
Run the report. (under Basics). You get every flagged item with Needed, Reorder point, Desired level, and QOH columns, plus a Comparison Location dropdown to check whether another store has the stock before you buy more.