Managing parts and truck inventory without losing your mind

Truck inventory works when every truck has a standard stock list with minimum quantities, parts used are recorded on the job when they're used, trucks are restocked from the shop on a fixed rhythm, and counts happen regularly enough to catch drift. You don't need a warehouse system. You need a list, a habit and a way to see what's running low.

Parts are often one of the biggest expenses in a service business, and also one of the least watched. Missing parts mean extra supply house runs and second trips. Parts used but never billed mean lost revenue. Here's a system that scales from one van to a fleet.

Why does truck inventory get out of control?

The usual causes:

• No standard list. Each tech stocks their truck the way they like, so nobody knows what's on any truck.
• Parts used but not recorded. The fitting goes in, but never onto the invoice or the job.
• Restocking by memory. Techs grab what they think they need at the shop or supply house.
• No counts. Nobody checks what's actually on the truck, so records and reality drift apart.
• Special orders mixed in. A part ordered for one job ends up used somewhere else.

Each of these is a habit problem more than a software problem, but the right tools make the habits much easier.

What should be on every truck?

Build a standard truck stock list for each truck type (for example, service van versus install truck). For each item, set:

• A target quantity you want on the truck after restocking
• A reorder point, the quantity at which it should be restocked

Start from your last few months of job history: which parts were used most often, and how many per week? Fast movers get higher quantities. Parts you use twice a year probably belong at the shop, not on every truck.

A few principles:

• Stock for the common call, not every call. Trying to carry everything means heavy trucks and lots of dead stock.
• Standardize brands and sizes where you can, so you stock fewer variations.
• Keep a few high-value parts centralized and move them to trucks when needed.

How should techs record parts used on a job?

The simplest rule: if it goes into a customer's home, it goes onto the job. Recording it at that moment, from the phone, does three things at once:

1. It bills the customer correctly.
2. It takes the part off the truck's count.
3. It feeds job costing, so you know what the job really cost.

Make it fast. Techs should pick parts from a list (your pricebook), not type descriptions. If recording a part takes more than a few seconds, it won't happen on busy days.

How do you restock trucks?

Pick a rhythm and stick with it. Common approaches:

• Weekly restock day. Each truck restocks from the shop on a set day, back to target quantities.
• Restock on request. Techs send a restock request when items hit their reorder point, and the shop prepares it.
• Both. A weekly baseline plus requests for urgent items.

A restock request should list what's needed and how many, ideally pre-filled from what's below its reorder point. The shop pulls the items, moves them to the truck in your records, and the tech picks them up. That transfer matters: if parts leave the shop but never "arrive" on the truck in your records, your counts are wrong from day one.

What about parts for a specific job?

Special orders, like a specific compressor or a custom-length part, should be tied to the job they're for:

• Order them on a purchase order linked to that job. Our guide to purchase orders for small contractors covers this.
• Label them with the job number and customer when they arrive.
• Keep them separate from general stock on the shelf.

This prevents the classic problem of a special-order part being grabbed for a different job, leaving the original customer waiting.

How often should you count?

Counting everything every month is unrealistic for most small shops. A practical approach:

• Cycle counts: count a few trucks or a few categories each week, so every truck gets counted every month or two.
• High-value items more often: count expensive parts weekly.
• Full count once or twice a year, often before year-end for your accountant.

When the count differs from your records, adjust it with a reason. Patterns in those reasons, like one truck that's always short, tell you where to look.

What if a tech uses a part the records say isn't there?

It happens. The truck had it, but your records didn't. Don't block the tech from recording the part. Let the record go negative and flag it. A negative count is a useful signal that something wasn't recorded properly, whether it was a restock that never got entered or a part grabbed from another truck.

How do you know if inventory is under control?

Watch a few signals:

• Supply house runs during the day. Fewer is better.
• Second trips because of missing parts. Track these as their own reason code if you can.
• Count adjustments. Large or frequent adjustments mean recording habits need work.
• Parts cost as a share of revenue on jobs where it should be fairly stable.

A truck inventory checklist

• Standard stock list per truck type, with target and reorder quantities
• Every part used is recorded on the job from the phone
• Fixed restock rhythm, with restock requests pre-filled from low items
• Transfers from shop to truck recorded every time
• Special orders tied to the job on a purchase order
• Cycle counts weekly, full count once or twice a year

FAQ

Should techs be responsible for their truck's inventory? Yes, in the sense that they record what they use and report what they need. Many shops share count results with techs so everyone sees the same numbers. Whether to tie shortages to pay raises legal and morale questions, so talk to an employment professional before you do.

How much stock should a truck carry? Enough for the common calls between restocks, and not much more. Use your own usage history rather than a rule of thumb.

What's the best way to value inventory? Common methods include average cost and last cost. Your accountant can tell you which suits your books and tax situation.

Do I need a separate inventory system? Not necessarily. If your field service software tracks stock by location and records parts used on jobs, that is often enough for a small or midsize shop.

How ServFlo helps

ServFlo's inventory (on the Pro plan) tracks stock by location: warehouses and each technician's truck. Every item at each location can have a reorder point and reorder quantity. When a tech adds a stocked part to a job from the technician app, it comes off their truck automatically, and a low stock list suggests what to reorder, with one click to draft purchase orders by vendor. Techs see their own truck's stock, can tap Restock my truck to send a pre-filled request, and the office can fill it straight from the warehouse as a transfer. Stock counts and adjustments with reasons keep records honest, and negative stock is allowed but flagged. See reports and job costing and pricing for details.

Photo by Acton Crawford on Unsplash.