Inventory management methods are the rules you use to decide what to keep, where to put it, when to reorder, how much to order and how to check the count. The most useful ones are ABC analysis (focus on what matters), reorder points with safety stock (order at the right time), EOQ (order the right amount), FIFO or FEFO (rotate stock correctly) and cycle counting (keep the numbers true).
No single method suits every business. A shop selling perishable food needs rotation rules above all, while a manufacturer with long supplier lead times cares most about reorder timing. This guide explains each method plainly, shows a worked example, and helps you combine a few into a system that fits your operation.
The main methods at a glance
| Method | Question it answers | Best for |
|---|---|---|
| ABC analysis | Which items deserve the most attention? | Any business with many SKUs |
| Reorder point and safety stock | When should I order? | Steady-demand products |
| Economic order quantity (EOQ) | How much should I order? | Regular, predictable demand |
| FIFO and FEFO | Which units leave first? | Perishables, dated or fast-ageing goods |
| Just-in-time | Can I hold less? | Reliable suppliers, short lead times |
| Cycle counting | Is the count correct? | All stock holders |
ABC analysis: decide where to spend attention
ABC analysis ranks items by their annual value of use, which is quantity sold multiplied by cost. A small number of items usually account for most of the value. Group them: A items are the top slice, B the middle and C the long tail of cheap or slow lines.
Then treat them differently. A items get tight control, frequent counts, close supplier relationships and accurate forecasts. C items can use simple rules, such as a two-bin system or a generous reorder quantity. This stops you spending the same effort on a £2 fastener as on your most expensive product.
Reorder point and safety stock
A reorder point tells you to place an order when stock falls to a set level. The formula is demand during lead time plus safety stock.
Worked example, with assumptions: you sell 20 units a day, the supplier takes 10 days to deliver and you want a safety buffer of 60 units because demand and delivery times vary. Demand during lead time is 200 units, so the reorder point is 260. When available stock reaches 260, you order.
Review these numbers when demand or lead times change. A stale reorder point is one of the commonest causes of stockouts. Software can track reorder points for you; see our guide to inventory management software.
Economic order quantity
EOQ finds the order size that balances two costs: the cost of placing an order (admin, shipping, set-up) and the cost of holding stock (storage, capital, damage). The standard formula is the square root of (2 × annual demand × cost per order ÷ holding cost per unit per year).
Worked example, with assumptions: annual demand 2,400 units, £30 to place an order, £1.50 to hold one unit for a year. Two times 2,400 times 30 is 144,000; divided by 1.5 is 96,000; the square root is about 310. Ordering around 310 units at a time minimises the two costs combined.
EOQ is a guide, not an order. Supplier minimums, pack sizes, discounts and storage space will adjust it, and it works best when demand is steady.
FIFO, FEFO and LIFO
FIFO (first in, first out) means the oldest stock is sold first. FEFO (first expired, first out) sends the unit with the earliest expiry date first, and is the right rule for food, chemicals and medical goods. Both are about physical movement, so they need shelves arranged so older stock is picked first, and records of dates or batches.
The same names are also used for costing. FIFO costing assumes the oldest cost leaves first. LIFO is a costing choice not generally accepted for UK accounting, so confirm with your accountant which valuation method applies to you.
Just-in-time and lean stock
Just-in-time keeps stock minimal by ordering close to when you need it. It reduces storage and capital costs but leaves little room for delays, so it requires dependable suppliers, accurate forecasts and good communication.
A cautious version suits most small companies: keep lean stock on predictable lines and a buffer on items with unreliable supply. Where supply is fragile, extra safety stock is cheaper than lost sales.
Cycle counting and stock accuracy
Counting everything once a year disrupts the business and still leaves errors for eleven months. Cycle counting spreads the work: count a small set of items each day or week, concentrating on A items and any with recent discrepancies.
- Rank items with ABC analysis.
- Set a frequency: A items monthly, B quarterly, C once or twice a year.
- Count a daily sample and compare it with the system.
- Investigate every difference above your tolerance.
- Correct the record and fix the cause, such as a picking mistake or unrecorded transfer.
Our stock count guide explains how to run the count itself.
Combining methods into one system
Most businesses use four or five methods together. A sensible starting set looks like this:
- ABC analysis to rank your range.
- Reorder points with safety stock on A and B items.
- EOQ as a sense check for order sizes.
- FIFO or FEFO for storage and picking.
- Cycle counting for accuracy.
Add forecasting and seasonality for products with predictable peaks. Review the settings quarterly, because demand shifts.
Common mistakes
- Applying the same rule to every item.
- Using reorder points without updating lead times.
- Counting too rarely to catch the cause of errors.
- Optimising for low stock while ignoring stockout cost.
- Treating methods as theory rather than writing them into daily routines.
Putting the methods into practice
Methods only work if the data is right and the routines are followed. We built Dika Ops so reorder points, purchasing, stock movements and counts sit on the same record; it is in closed beta with a waitlist. If your processes need something specific, our custom software team builds tools around them, and you can find our contact details on our homepage.
Frequently asked questions
What are the main inventory management methods?
The main methods are ABC analysis, reorder point with safety stock, economic order quantity, FIFO and FEFO, just-in-time, and cycle counting. Most businesses combine several of them.
What is the best inventory management method?
There is no single best one. ABC analysis plus reorder points and cycle counting is a strong starting set for most businesses, with FEFO added for perishable goods.
What is the difference between FIFO and FEFO?
FIFO sells the oldest received stock first, while FEFO sells the stock that expires first. They differ when a newer delivery has an earlier expiry date, which is common with food and chemicals.
How do I calculate a reorder point?
Multiply average daily demand by supplier lead time in days, then add safety stock. If you sell 20 units a day, lead time is 10 days and safety stock is 60, the reorder point is 260.
How do I calculate safety stock?
A simple approach is to take your highest realistic daily demand and longest realistic lead time, work out the stock needed for that case, and subtract the average case. More precise methods use the variation in demand and lead time. Start simple and adjust after a few cycles.
How often should I count inventory?
It depends on value and risk. Count high-value items more often, perhaps monthly, and slow cheap items less often. A cycle count schedule makes this routine rather than disruptive.
Next step
Run an ABC ranking on your current range this week. It takes an afternoon, shows where your attention is going, and tells you which of the other methods to apply first.
