Manufacturing working capital is the tightest of any UK sector, with a cash conversion cycle of 86 days – meaning cash is locked up for nearly three months between paying for raw materials and collecting payment from customers.
If you run a manufacturing business, this is not news to you. You live it every day: buying steel, plastic, components, or ingredients weeks before production even starts, transforming them through a process that takes days or weeks, storing finished goods until they ship, and then waiting another month or two for your customer to pay. At every stage, cash is trapped.
The good news is that manufacturing also has more levers available to reduce its working capital cycle than almost any other sector. The bad news is that pulling those levers takes discipline, investment, and a willingness to challenge long-standing habits.
The UK Manufacturing Working Capital Benchmarks
Here are the industry averages for UK manufacturers:
| Metric | Benchmark | What it means |
|---|---|---|
| Days Sales Outstanding (DSO) | 52 days | Nearly eight weeks to collect payment |
| Days Inventory Outstanding (DIO) | 72 days | Stock sits for over ten weeks across the cycle |
| Days Payable Outstanding (DPO) | 38 days | You pay suppliers in about five weeks |
| Cash Conversion Cycle (CCC) | 86 days | Cash is tied up for nearly three months |
That CCC of 86 days is enormous. For context, retail manages 15 days. Professional services manages 23 days. Even construction, with all its payment problems, sits at 38 days. Manufacturing is in a class of its own – and the DIO of 72 days is the biggest single reason why.
You can benchmark your own business using the CCC Calculator.
The Triple Cash Trap
What makes manufacturing working capital so demanding is that cash is not trapped in one place. It is trapped in three simultaneously.
Raw materials. You buy steel, chemicals, timber, electronic components, or whatever your inputs are. These sit in your stores waiting to enter production. If your supplier has a six-week lead time, you might be holding two months’ worth of raw materials just to avoid running out.
Work in progress (WIP). Once materials enter production, they are no longer raw materials but they are not yet finished goods. During your production cycle – which might be a few days for simple products or several weeks for complex ones – cash is trapped in this intermediate state. You cannot sell WIP and you cannot return it to the supplier.
Finished goods. Once production is complete, finished goods sit in your warehouse until they ship to a customer. If you make to stock rather than make to order, you might hold weeks of finished goods inventory.
A Worked Example: Where the 72 Days Hide
Mark runs a precision engineering firm in the West Midlands with annual revenue of £3 million and cost of goods sold of £2.1 million. His DIO is 72 days, meaning he holds roughly £414,000 of inventory at any given time. Here is how it breaks down:
- Raw materials (28 days): £161,000. His key supplier has an eight-week lead time, so he orders in bulk to avoid production stoppages.
- Work in progress (18 days): £104,000. His average production cycle is about two and a half weeks from first cut to final inspection.
- Finished goods (26 days): £149,000. He produces in batches and holds stock for his major customers who order irregularly.
If Mark could reduce his total DIO from 72 days to 55 days – still well above the retail or services average – he would free up approximately £98,000 in cash. That is money currently sitting on shelves and on the shop floor that could be in his bank account.
Use the DIO Calculator to run your own numbers.
Strategies to Reduce Your DIO
ABC Analysis for Inventory Prioritisation
Not all inventory deserves the same attention. ABC analysis divides your stock into three categories:
- A items (roughly 20 per cent of SKUs, 80 per cent of value): These are your high-value materials and components. Monitor them closely, order frequently in smaller quantities, and track usage in real time.
- B items (roughly 30 per cent of SKUs, 15 per cent of value): Review these monthly and keep moderate safety stock.
- C items (roughly 50 per cent of SKUs, 5 per cent of value): These are low-value items like fasteners, consumables, and packaging. Buy these in bulk because the cash impact is small and running out causes disproportionate disruption.
Many manufacturers treat all inventory the same way – either under-managing everything or trying to optimise every last item. ABC analysis focuses your effort where the cash impact is greatest.
Just-in-Time Where Supply Allows
Just-in-time (JIT) inventory management – ordering materials to arrive as close as possible to when they enter production – is the most effective way to reduce raw material DIO. But it only works when your supply chain is reliable.
If your key materials have long or unpredictable lead times, going fully JIT is risky. Instead, apply JIT selectively: use it for materials with short, reliable lead times and domestic suppliers, while maintaining buffer stock for materials with long or volatile supply chains.
For your A items from reliable suppliers, aim to hold no more than one to two weeks of stock. For items with six-week lead times from overseas, a larger buffer is prudent – but quantify what that buffer should be rather than defaulting to “order lots just in case.”
Consignment Stock Arrangements
Under a consignment stock arrangement, your supplier places materials in your warehouse, but you only pay for them when you use them in production. The stock is on your shelf but on your supplier’s balance sheet.
This effectively reduces your raw material DIO to near zero for those items. The supplier benefits because they have a guaranteed outlet and can plan their own production better. You benefit because you have materials available without tying up cash.
Consignment arrangements are most feasible with large suppliers who have the financial strength to carry the stock. If you are a significant customer, this is a negotiation worth having.
Reduce Production Lead Times
Every day your production cycle takes is a day of cash trapped in WIP. Lean manufacturing principles – reducing set-up times, eliminating bottlenecks, improving flow, reducing batch sizes – directly reduce WIP and free up cash.
You do not need a full lean transformation to make progress. Start by mapping your highest-value production processes and identifying where work sits idle between operations. If a component spends three days being machined and four days waiting between machines, you have more queue time than process time. Reducing that queue time is often the fastest route to lower WIP.
Better Demand Forecasting
Finished goods inventory exists because you are making products before customers order them. The less accurate your demand forecast, the more finished goods you hold as insurance against getting it wrong.
Improving forecasting does not require expensive software. Start with the basics: track forecast versus actual sales by product line, look for patterns and biases (do you consistently over-forecast certain products?), and involve your sales team in the process. Even modest improvements in forecast accuracy – say, reducing forecast error from 30 per cent to 20 per cent – can justify reducing finished goods buffers significantly.
Managing Raw Material Price Volatility
Manufacturing is uniquely exposed to commodity price swings. Steel, aluminium, polymers, timber, and energy costs can move 20 to 30 per cent in a year. This creates a working capital problem on top of a margin problem.
When raw material prices are rising, you face pressure to buy ahead – locking in today’s price but tying up more cash in inventory. When prices are falling, you risk holding stock worth less than you paid for it.
There is no perfect answer, but practical approaches include:
- Fixed-price supplier contracts for three to six months where available.
- Price escalation clauses in your customer contracts so raw material increases can be passed through.
- Smaller, more frequent orders rather than large bulk purchases, accepting slightly higher per-unit costs in exchange for lower cash exposure.
Managing Long Supplier Lead Times Without Over-Ordering
When a key component has a 12-week lead time from an overseas supplier, the temptation is to hold three to four months of stock to be safe. But that safety stock might represent £100,000 or more of trapped cash.
Alternatives to over-ordering include: identifying secondary domestic suppliers who can provide smaller quantities at shorter notice (even at a higher price, as a backup); sharing your production forecasts with your main supplier so they can hold buffer stock at their end rather than yours; and splitting orders so you place a firm order for immediate needs and a provisional order for the next period that can be adjusted.
The goal is not to eliminate safety stock entirely – stock-outs in manufacturing are genuinely costly. The goal is to quantify the right level of safety stock rather than guessing, and to explore arrangements that shift some of the holding cost upstream.
Practical Takeaways for Manufacturing Working Capital
- Break your DIO into raw materials, WIP, and finished goods and tackle each separately. Use the DIO Calculator.
- Apply ABC analysis to focus cash-saving effort on high-value inventory items.
- Use JIT selectively for materials with reliable, short lead times.
- Negotiate consignment stock with major suppliers for your highest-value raw materials.
- Reduce production lead times – queue time between operations is often where the biggest gains hide.
- Improve demand forecasting to justify lower finished goods buffers.
- Manage commodity price risk through contracts and pass-through clauses rather than by hoarding stock.
- Benchmark your CCC regularly against the industry average of 86 days using the CCC Calculator and read the full cash conversion cycle guide for deeper context.
For manufacturers with seasonal demand patterns, the interplay between production scheduling, inventory building, and cash flow timing adds another layer of complexity worth exploring.
This article is for general information only and does not constitute financial advice. Working capital benchmarks are industry averages and individual businesses may differ significantly. If you are experiencing cash flow difficulties, consult a qualified accountant or financial adviser.