Inventory Control for Manufacturers: Cut Waste, Ship On Time

Inventory Control for Manufacturers: Reduce Waste, Strengthen Supply Chains, and Deliver on Time

Inventory control for manufacturers is the process of monitoring and managing raw materials, work-in-progress, and finished goods so you always have the right stock at the right time.

To cut waste and ship on time, growing manufacturers track inventory across every production stage and use reorder rules to prevent both stockouts and overstock.

Here's the step-by-step process to make it work.

The manufacturing industry loses significant money every year from poor inventory practices — overstocked raw materials sitting in warehouses, stockouts that freeze production lines, and expired inventory discovered days before a shipment is due. These are not edge cases. They happen constantly in shops that rely on manual tracking and gut-feel reordering.

The good news: getting inventory control right does more than cut waste. It strengthens your entire supply chain, improves supplier relationships, and directly raises the level of service your customers experience. Here is how it all connects — and what you can do about it.

What is manufacturing inventory control?

Manufacturing inventory control is the set of practices and systems you use to track, organize, and regulate every item that moves through your facility — from the moment raw materials arrive to the moment finished goods leave your dock.

It differs from general inventory management because manufacturers deal with transformation. You're not just storing and shipping products. You're converting inputs into outputs through production processes, which means your inventory changes form as it moves through your operation.

The core goal is maintaining equilibrium: enough stock to keep production running smoothly, but not so much that you're paying to store materials you don't need yet.

What makes manufacturing inventory different

Manufacturing inventory is not the same as retail or ecommerce inventory. You are managing multiple categories of stock at the same time:

Raw materials — Items waiting to enter production. These need to be ordered in the right quantities, at the right time, from the right suppliers.

Work-in-progress (WIP) — Materials actively moving through the production process or queued for the next batch.

Finished goods — Completed products ready for sale, sitting at your facility, a central warehouse, or distributed across multiple locations.

MRO supplies — Maintenance, repair, and operations items (tools, cleaning supplies, spare parts) that keep your production line running.

Each category has its own lead times, shelf lives, and reorder logic. Managing all of them with spreadsheets or manual counts is where things fall apart — and where the right inventory management software pays for itself.

Key inventory control challenges for manufacturers

Most inventory problems in manufacturing trace back to a few root causes:

Relying on manual processes

When stock levels, reorder points, and lead times live in someone's head (or a spreadsheet that hasn't been updated since last Tuesday), errors multiply. Purchase orders get placed based on guesses rather than data. Raw materials get over-ordered because nobody could find the pallet that was pushed to the back of the warehouse.

If this sounds familiar, you're not alone — it's one of the most common reasons manufacturers move away from spreadsheets as they grow.

Poor visibility across the production cycle

Without real-time tracking, you cannot see how much raw material went into a production run, how much WIP is on the floor, or how many finished units are ready to ship. That blind spot ripples through every downstream decision — from purchasing to sales commitments.

Made-to-order complexity

More manufacturers are shifting from assembly-line production to made-to-order workflows where products are customized to buyer specs. Traditional demand forecasting breaks down in this model. You need a system that can handle variable bills of materials and dynamic material requirements — not static reorder rules.

Warehouse disorganization

Lost inventory, damaged stock, and warehouse space consumed by materials you did not need to order yet — these are symptoms of the same problem. Without clear visibility into what is stored where, warehouse operations become a bottleneck instead of an asset.

Want real-time visibility into every SKU? See how Brahmin tracks inventory across all your channels →

Common inventory control methods for manufacturers

There is no single "right" method for controlling manufacturing inventory. The best approach depends on your product type, production volume, and supply chain complexity. Here are the methods that growing manufacturers use most often:

Just-in-Time (JIT)

JIT aims to receive materials only when they're needed for production, minimizing storage costs and waste. It works well when your suppliers are reliable and lead times are predictable. The risk: if a supplier is late or short-ships, you have no buffer.

Economic Order Quantity (EOQ)

EOQ is a formula that calculates the ideal order quantity to minimize the total cost of ordering and holding inventory. It balances the cost of placing frequent small orders against the cost of storing large ones. EOQ works best for materials with steady, predictable demand.

EOQ formula: √(2DS / H)

D = annual demand (units)

S = cost per order (purchasing, shipping, receiving)

H = annual holding cost per unit

For example, if you use 10,000 units per year, each order costs $50 to place, and holding one unit costs $2 per year, your EOQ is √(2 × 10,000 × 50 / 2) = 707 units per order.

FIFO and FEFO

FIFO (First In, First Out) means you use the oldest stock first. FEFO (First Expired, First Out) prioritizes items closest to their expiration date. Both methods reduce waste from expired or obsolete materials.

FEFO is especially critical for food, supplement, and cosmetics manufacturers who need to track shelf life. If you're in one of those industries, lot tracking is what makes FEFO enforceable at scale.

ABC Analysis

ABC analysis classifies your inventory into three groups:

A items — High value, low volume (roughly 20% of items, 80% of value)

B items — Moderate value and volume

C items — Low value, high volume

You apply tighter controls and more frequent reviews to A items, lighter controls to C items. This keeps your effort focused where it matters most.

Safety stock and reorder points

Safety stock is extra inventory you hold as a buffer against demand spikes or supplier delays. Your reorder point is the stock level at which you trigger a new purchase order.

Reorder point formula: (Average daily usage × Lead time in days) + Safety stock

For example, if you use 50 units per day, your supplier takes 10 days to deliver, and you keep 200 units of safety stock, your reorder point is (50 × 10) + 200 = 700 units.

MRP software calculates these automatically based on your BOMs, sales orders, and supplier lead times — so you don't have to update reorder points manually every time demand shifts.

How better inventory control strengthens your supply chain

Inventory control and supply chain performance are inseparable. When you have accurate, real-time data on your stock levels, you gain visibility not just into your inventory — but into the health of your entire supply chain.

Spot inefficiencies before they become emergencies

With granular lot tracking and inventory data, you can identify non-performing suppliers, unnecessary process steps eating up time, and bottlenecks that hurt your margins. If your shipping commitments keep slipping, proper inventory tracking reveals whether the root cause is a supply problem, a production scheduling issue, or a warehousing gap.

Maintain equilibrium between physical and information flows

A supply chain moves goods and information. When those two flows fall out of sync — a customer changes a delivery address, demand spikes unexpectedly, a supplier shorts an order — the entire chain feels it. Real-time inventory data keeps both flows aligned so you can adapt quickly rather than scrambling after the fact.

Manage supplier relationships proactively

Your suppliers need current demand information to serve you well. If you know you are about to run low on a critical material, giving your supplier advance notice means they can fulfill your order without rush charges or delays. When you spring last-minute orders on suppliers because you did not track your own stock, the pressure cascades through every link in the chain — and your customers feel it at the end.

The inventory control process: five practical steps

1. Move from physical counts to automated tracking

The starting point is minimizing human intervention in inventory management. Barcode scanning, RFID tags, and dedicated inventory management software replace guesswork with data. Serialized barcoding, for instance, gives you complete knowledge of how much raw material entered production, how much was consumed, and how much remains.

That doesn't mean you eliminate physical counts entirely. Cycle counting — counting a small subset of inventory on a rotating schedule — catches discrepancies before they compound. The difference is that cycle counting validates your system data rather than being your only source of truth.

2. Get real-time inventory updates

You need end-to-end visibility — from the moment raw materials arrive at your facility through WIP on the production floor to finished goods ready for shipment. Real-time tracking digitizes this information so you always know your inventory status. This is especially critical for manufacturers dealing with perishable materials or regulated industries where lot traceability is required.

3. Set up disruption alerts

Even the best inventory plan can be disrupted. A supplier sends the wrong quantity. A production line goes down. Market demand shifts overnight. Your system needs to notify the right people immediately — by email, text, or push notification — when an unplanned change threatens your inventory levels.

Consider this scenario: your raw material supplier ships significantly less than you ordered. Without an alert, your production line keeps running at full speed until materials run out. With an alert, you can source from an alternate supplier before production is affected.

4. Use inventory data to optimize production planning

Inventory control is not an end in itself — it exists to support optimal production. Accurate inventory data gives you what you need to plan production: material availability, raw material costs (including warehousing), supplier lead times, and current stock levels. Feed this data into your production planning process and you can schedule runs with confidence instead of hope.

5. Build forecasting into your purchasing process

Demand forecasting drives smart inventory levels. Analyze your sales history to predict which products will see increased demand — especially around seasonal peaks. Then automate your purchasing so reorder points, minimum order quantities, and lead times are all factored in without manual intervention. Modern MRP software handles this automatically, keeping your inventory lean without risking stockouts.

How to measure your manufacturing inventory performance

You can't improve what you don't measure. Track these key metrics to see whether your inventory control is actually working:

Inventory turnover ratio — How many times you sell and replace your inventory in a period. A higher ratio typically means you're converting stock into revenue efficiently. (Learn more about inventory turnover)

Days of inventory on hand — How many days your current stock would last at the current rate of consumption. Lower is better, as long as you're not causing stockouts.

Stockout rate — The percentage of orders you can't fulfill because materials or finished goods aren't available. Track this weekly.

Carrying cost as a percentage of inventory value — Includes warehousing, insurance, depreciation, and opportunity cost. Most manufacturers target 20–30%.

Order accuracy — The percentage of orders shipped correctly the first time. Poor inventory data is the top cause of picking errors.

Review these monthly. If your inventory turnover is dropping or your stockout rate is climbing, those are early signals that your control processes need attention.

The customer service connection

Everything above — tighter inventory control, smoother supply chains, better supplier coordination — has one ultimate outcome: better customer service.

When your inventory is accurate, you do not sell products you cannot deliver. When your supply chain runs smoothly, orders ship on time. When you have visibility into stock levels, you can restock fast-moving items before they go out of stock — instead of telling customers to check back later.

Here is a real-world example: a customer wants to order a product but it is out of stock. They need it before a seasonal deadline a few weeks away. With strong inventory visibility, you spot the stockout immediately, trigger a replenishment order, and get the product back in stock well before the deadline. The customer gets what they need on time. That is what inventory control looks like from the customer's perspective.

For manufacturers specifically, this connection is even more direct. If your raw material inventory is off, production schedules slip. When production slips, delivery commitments break. When deliveries break, customers leave. The chain is only as strong as your weakest inventory process.

Choosing the right inventory control system

Not every inventory system is built for manufacturing. Retail-focused tools will not handle BOMs, WIP tracking, or multi-stage production workflows. Look for a system that covers:

Real-time inventory tracking across raw materials, WIP, and finished goods

Automated reorder points tied to demand forecasts and supplier lead times

Lot and batch traceability for compliance and recall readiness

Production planning integration so inventory data feeds directly into scheduling

Multi-location support if you operate across facilities or warehouses

BOM management to connect your inventory with your product structures

The goal is a single source of truth for your inventory that every team — purchasing, production, sales, shipping — can rely on.

Frequently asked questions

How do you control inventory in a manufacturing company?

You control inventory in a manufacturing company by tracking stock levels in real time across raw materials, WIP, and finished goods — then setting automated reorder points based on demand forecasts and supplier lead times. Combine this with cycle counting, lot tracking, and ABC analysis to keep high-value items tightly managed. The right inventory management software ties all of these practices together so nothing slips through the cracks.

What is FEFO and FIFO?

FIFO (First In, First Out) means you use or sell the oldest inventory first, regardless of expiration date. FEFO (First Expired, First Out) prioritizes inventory closest to its expiration date, even if it arrived later. FEFO is standard in food, beverage, supplement, and cosmetics manufacturing where shelf life determines whether a product can legally ship.

What is the difference between inventory control and inventory management?

Inventory control focuses on what you already have in stock — tracking quantities, locations, and conditions of items in your warehouse. Inventory management is the broader discipline that includes control plus demand forecasting, purchasing, supplier management, and strategic planning. Think of inventory control as a subset of inventory management.

What is the best inventory method for manufacturing?

There is no single best method — it depends on your production model, product type, and supply chain. Many growing manufacturers combine methods: ABC analysis to prioritize attention, EOQ to size orders, safety stock formulas to set buffers, and MRP to automate the math across all items. Start with the method that addresses your biggest pain point, then layer on others as you grow.

How Brahmin Solutions can help

Brahmin Solutions is a cloud-based manufacturing platform built for growing manufacturers doing $500K–$50M in revenue. It brings inventory management, MRP, production planning, lot tracking, and purchasing together in one system — without the cost or complexity of enterprise ERP.

If you're ready to move beyond spreadsheets and get real control over your manufacturing inventory, book a demo and see how it fits your operation.