A good stock replenishment workflow is a short chain that never breaks: a trigger tells you a part is running low, a rule decides how much to order, someone approves it, the goods arrive against the order, and the stock record updates before the next job needs the part. For a service business that chain has an extra link most guides ignore: the van. This article walks through each step as it works for engineers, vans and a central store, not for a retail shelf or a distribution warehouse.
TL;DR
- Replenishment is a repeating loop: monitor, forecast, reorder, approve, receive, record, review. Each hand-off needs an owner and a rule.
- Pick the trigger per part: min/max or reorder point for fast-moving consumables, a tighter manual review for high-value or critical parts.
- Treat each van as a stock location with its own minimum and maximum, not as a corner of the main store.
- Link purchase orders to jobs and receipts, so what arrives is matched to what was ordered and the record is right the same day.
- Review a few numbers monthly (stockouts on jobs, return trips for parts, excess held) and adjust levels from real usage.
Table of Contents
- What a replenishment workflow actually is
- The stages, step by step
- Not every part deserves the same rule
- Where replenishment workflows break in service businesses
- A weekly rhythm that works
- What to measure
- Our perspective
- Putting it in one system
- Getting started this month
- FAQ
- Sources
What a replenishment workflow actually is
Stock replenishment is the cycle of monitoring stock, forecasting demand and refilling what has been used, so you avoid both stockouts and costly overstock. Shopify's guide breaks an effective cycle into nine steps: monitoring current levels, forecasting demand, setting reorder points, creating purchase orders, securing approval, receiving goods, updating databases, housing stock in physical locations, and optimising the whole process.
That list was written with retail in mind, but the skeleton fits a service business well. What changes is where the stock sits and what triggers its use. A shop sells a unit to a customer. An engineer fits a part on a job, often hours from the depot, and the part has to be in the van before the booking, not after the complaint.
So a service replenishment workflow has two halves:
- Demand side: jobs, planned maintenance visits and contract work consume parts. Usage should be recorded against the job.
- Supply side: stores, vans and suppliers replace what was used, in quantities and at times that your rules define.
When the two halves share one record, replenishment becomes routine. When they sit in separate spreadsheets, it turns into a weekly argument about who ordered what.
The stages, step by step
1. Capture usage at the point of use
Everything downstream depends on this. If an engineer fits a fan motor and nobody records it until the end of the week, the van still shows the motor as present, the minimum is not breached, and no order goes out. Usage should be booked against the job from the engineer's phone, ideally while still on site, including when there is no signal. The record then feeds both the invoice (parts used) and the stock level (parts gone).
The simplest test of your current process: pick last week's ten jobs and ask whether you can see, without phoning anyone, which parts were used on each. If not, fix capture before touching any reorder rules.
2. Set a trigger for every stocked part
A trigger is the condition that starts a reorder. Microsoft's documentation on replenishment strategies describes four standard models: min/max, which triggers when stock falls below a defined minimum; wave demand, which creates work for specific outbound orders; load demand, which aggregates demand across loads; and reorder point, which raises a request once on-hand plus on-order quantity falls to a set threshold.
For most UK service businesses, two of these matter:
- Min/max suits vans and small stores. When a van drops below its minimum, it is topped up to its maximum. Simple, visible and easy for engineers to understand.
- Reorder point suits the central store, where supplier lead time matters. You reorder when stock plus anything already on order hits the threshold.
The demand-driven models are closer to what you do for a specific project: a boiler replacement or a refrigeration install where you order the exact parts for a known job, rather than holding them in general stock.
3. Decide how much to order
The reorder point formula most teams use is average daily usage multiplied by supplier lead time in days, plus safety stock. Safety stock is the reserve held against variability in supply and demand, a concept covered alongside the economic order quantity (EOQ) model in these supply chain lecture notes. EOQ balances the cost of placing orders against the cost of holding stock.
A worked example with invented numbers, purely for illustration: a contractor uses an average of 3 contactors a week across its engineers, roughly 0.6 a working day. The supplier's lead time is 4 working days. Usage over lead time is about 2.4, so with a safety buffer of 2, the reorder point is about 4.4, which you round up to 5. When stock plus open orders reaches 5, reorder. The order quantity might be 10, because the supplier's carriage charge makes smaller orders poor value.
Do not obsess over precision. A rule that is roughly right and followed beats a perfect one that nobody uses. Revisit it quarterly with actual usage.
4. Raise and approve the purchase order
Once the trigger fires, a purchase order should be raised with the supplier, part number, quantity, price and delivery location filled in. Who approves it depends on value. A common pattern is automatic release for low-value consumables below a set limit, and a named approver above it. Write the limits down. Approval delays are one of the commonest reasons a trigger fires and a van still runs empty.
If you want a closer look at what goes wrong between order and supplier acknowledgement, our piece on purchase order matching and acknowledgements covers the failures we see most.
5. Receive against the order
When goods arrive, check them against the purchase order, not against the delivery note alone. Record the quantity actually received, note any shortfalls or damage, and book the stock into a specific location: the main store, a bin, or a van. A part that is "somewhere in the building" is as useless as one that was never ordered.
Receipts matter for the money side too. Matching the order, receipt and supplier invoice before paying is what stops you paying for parts that never arrived.
6. Move stock to where it is used
This is the step that separates service from retail. Central stock is replenished from suppliers, and vans are replenished from central stock (or occasionally straight from a trade counter). Each transfer should be recorded, so the van's level is accurate when the engineer sets out. We cover how to set up the van layer in starting van stock control with 20 to 40 SKUs.
7. Review and adjust
The last step feeds the first. Look at what was used, what ran out, what sat untouched, and change minimums and maximums accordingly. This is the "optimisation" step in the nine-step cycle, and it is the one most businesses skip.
Not every part deserves the same rule
A single rule for every part is the most common design mistake. Industry practice in engineering is to tailor replenishment to part value and turnover, as described in a Jungheinrich UK case on engineer stock audits: high-value or critical parts warrant different audit and replenishment frequencies from high-turnover consumables. In a van, that also means space is used for parts needed on frequent jobs, which cuts return trips to base.
A practical way to split your range:
| Part type | Examples | Suggested approach | Review cadence |
|---|---|---|---|
| Fast-moving consumables | Fixings, fuses, seals, filters, PAT labels | Min/max per van, automatic top-up | Monthly |
| Common repairs | Contactors, thermostats, pumps, igniters | Min/max per van, reorder point in store | Monthly to quarterly |
| High-value or critical | Compressors, control boards, major valves | Held centrally, ordered against known jobs or contract risk | Each order, plus quarterly count |
| Compliance-linked items | Refrigerant, consumables tied to certificates | Min/max plus usage logged against the asset | Monthly, with records checked |
The last row deserves a note. Where a part is used on a regulated asset, such as refrigerant on an air conditioning or refrigeration system, the usage record is also a compliance record. Our refrigeration software page shows how F-Gas records and asset history sit together. In that case, replenishment and compliance share the same data, and getting one wrong damages the other.
Where replenishment workflows break in service businesses
From the operational side, the failures are rarely about formulas. They are usually these:
- Usage recorded late or not at all. The stock level lies, so triggers never fire.
- Engineers over-stocking out of caution. After one bad day without a part, they hoard. Vans fill with slow movers while the common parts run out.
- Tops-up on request rather than on consumption. Whoever shouts loudest gets restocked.
- Orders raised outside the system. A quick phone call to a trade counter that never reaches the record.
- No owner. Everyone assumes someone else is checking the store.
- Counts that need the vans back. If counting costs a day of an engineer's time, it will not happen.
Each has a workflow answer: capture on the job, set per-van maximums so hoarding has a ceiling, base top-ups on usage, route every order through one place, name an owner per location, and allow counts from the phone.
A weekly rhythm that works
Most teams do not need a sophisticated system to start. A simple weekly cycle:
- Monday: the stores owner reviews the list of parts below minimum, across the store and all vans.
- Monday afternoon: purchase orders are raised and approved against the limits.
- Midweek: deliveries are received against orders and booked into locations.
- Thursday: vans are topped up from the store, with transfers recorded.
- Friday: a short exception list is checked: jobs that waited on parts, parts returned unused, and anything ordered urgently outside the cycle.
The Friday list is where improvement comes from. If the same part appears three weeks running, its minimum is wrong.
What to measure
Resist the temptation to build a wall of charts. Four numbers will tell you most of what you need:
- Jobs delayed or revisited because a part was missing. This is the cost of too little stock.
- Stock value held, and how much has not moved in six months. This is the cost of too much.
- Purchase orders raised urgently, outside the cycle. A measure of how well your rules match reality.
- Receipts matched to orders on the day. A measure of record quality.
If you are choosing where to begin with reporting more broadly, three field service reporting metrics is a sensible starting point for operations managers.
Our perspective
Curcle was born inside a real UK service and engineering business, and replenishment is a good example of why that matters. We have seen the stock spreadsheet that was accurate on the day it was built and wrong a week later, and the van that carried 40 of a part nobody used and none of the one everybody needed.
Our view is that replenishment should not be its own project, owned by one person with a spreadsheet. It should fall out of the work. When an engineer records a part on a job, the van level changes, the minimum is checked, and the system tells the office what needs attention. That is the principle behind our approach to software generally: every click should earn its place, and the software should help a business see what needs attention, not merely record what has already happened.
We also think automation should assist rather than replace judgement. A system can flag that a van is below its minimum. It cannot know that a large contract starts on Monday and the van will need double the usual number of filters. Your stores owner or operations manager does. The best workflows put the routine in the background and leave the decisions to people who know the work.
Finally, we would rather you started small. Twenty to forty well-chosen parts, with owners and rules, beat a catalogue of 2,000 items nobody maintains.
— Luke Herridge
Putting it in one system
A replenishment workflow spans jobs, stock, purchasing and invoicing, which is why it falls apart when each lives in a different tool. If you want to see how these connect, the Curcle workflows page explains the single continuous record, and the features overview lists the stock, jobs, compliance and invoicing tools together. Our Operations Room is built around surfacing what needs a decision today.
Plans start from £99 per month for Starter, from £249 per month for Professional and from £499 per month for Business, with Enterprise available on request. You can compare them on the Curcle pricing page.
Getting started this month
You do not need to redesign everything. A first pass could look like this:
- List the 20 to 40 parts that cause most of your return trips and waiting jobs.
- Set a minimum and maximum for each van, and a reorder point for the store.
- Name one owner for the store and one for each group of vans.
- Require every order to go through a single route, with written approval limits.
- Record usage on the job, every time.
- Hold a fifteen-minute review each Friday for the first eight weeks, then monthly.
If some of your stocked items sit on assets that are inspected or certified, it is also worth linking parts used to the asset record. Asset lifecycle tracking explains why that closes audit gaps.
FAQ
What is the difference between min/max and reorder point replenishment?
Min/max tops stock up to a maximum once it falls below a minimum, which works well for vans and small stores. Reorder point raises an order when on-hand stock plus anything already on order falls to a threshold set from usage, lead time and safety stock. Reorder point is better where supplier lead times are long or variable.
How often should van stock be replenished?
There is no single answer, because it depends on how fast parts are used and how far vans are from the store. Many teams top up weekly and review the minimums monthly. High-turnover consumables may need more frequent top-ups than high-value spares, which are usually held centrally and ordered against known jobs.
What is safety stock and do service businesses need it?
Safety stock is a reserve held against uncertainty in supply and demand. Service businesses need it for parts where a stockout means a failed visit, a second trip or a missed service level. Keep it small and reviewed, since excess safety stock simply becomes dead stock.
Can replenishment be fully automated?
Routine triggers and purchase order drafting can be automated, and it is sensible to do so for low-value consumables. Decisions about unusual demand, new contracts or expensive parts still benefit from human review. We would treat automation as a way to surface what needs attention, not to remove the person responsible for stock.
Sources
- Stock Replenishment: What It Is and Best Practices, Shopify
- Replenishment overview, Microsoft Learn
- Supply Chain Management: Inventory Management, lecture notes
- Jungheinrich UK goes mobile to transform the carbon footprint of its engineer audits, Sustainable Logistics International