WhatsApp Stock Alerts: Automate Van Inventory Free in 2026

Who this is for

• UK trades firms running one to ten vans who are tired of finding out you are out of fittings only when someone opens the last box
• Owners, ops leads or supervisors who already live in WhatsApp and Google Sheets, and want automation without paying £30 to £80 per user each month
• Teams getting ready for Making Tax Digital and better record keeping, but not yet ready to jump into a full-blown job management suite

What this guide covers

• How to structure a van stock sheet that actually works on a phone
• How to use barcodes for fast, low friction stock updates in the van
• How to send automatic low stock alerts into WhatsApp using free or low cost tools
• How to handle photos and evidence so they are useful for HMRC, VAT and disputes
• When to stick with DIY and when it is time to step up to a paid field service platform

Why WhatsApp is winning in UK trades in 2026

Walk any UK site in 2026 and the most important tool is not the SDS drill, it is WhatsApp. Ofcom data shows that more than 90 percent of UK online adults now use it, with daily reach above 70 percent. In trade teams it has quietly replaced SMS, email and even some job apps for day to day communication, photos and “where are you” questions.

That creates a simple truth: if your stock alerts do not land in WhatsApp, they will probably be ignored.

At the same time, the economics of software have bitten hard. Solid trade suites like Tradify, Joblogic and Commusoft typically run £34 to £80 per user each month. They absolutely earn their keep at scale, but for a three van firm trying to control material costs and stay on top of MTD, those licences can feel like paying for a second mobile bill for every engineer.

That is where a WhatsApp plus Google Sheets workflow comes in. You already pay for the phones. Sheets is effectively free. The WhatsApp Business Cloud API uses a pay as you go model, with service messages inside a 24 hour chat window at zero cost and business initiated template messages charged per send. Build your flow right and most day to day alerts cost you nothing beyond time to set it up.

Build a lean van stock sheet that crews will actually use

The sheet is the backbone. If it is clunky, everyone falls back to “I will remember”. They will not.

At minimum, build one tab per van with:

• SKU and description for every regularly used item
• Quantity on van, minimum level and location on the rack
• Last checked and updated by to keep some light accountability

You can start from scratch in Google Sheets or adapt a free template from tools like Zoho Inventory, Sortly or Odoo Community. Strip anything that does not serve a decision on the driveway. If you have more than 200 SKUs, split into categories so the list still works on a phone.

Use Data Validation to lock SKUs and descriptions, and basic filters so engineers can type “tee 15” and jump straight to the right line. The aim is to make updating stock almost as fast as just driving to the merchant.

Add barcodes so updates are one scan, not ten taps

Barcode labels sound over the top until you have done a month with them. Suddenly everyone stops guessing.

On the hardware side you have two options:

• Phone as scanner: use built in camera tools like Google Lens or a free app to read Code 128 barcodes and paste the SKU into the sheet
• Cheap handheld scanner: plug into a tablet or rugged phone in the van and scan straight into the active cell

For labels, durability matters. Many Reddit users and field teams report that generic matte paper labels peel or fade in hot vans and damp basements. UK suppliers like The Barcode Warehouse, Labelzone and AA Labels stock Zebra Z Perform and Z Select ranges that stand up to abrasion, moisture and sunlight far better.

Use one label per SKU location on the van shelf. When an engineer takes stock, they scan the shelf, type the new quantity and move on. No trying to remember catalogue numbers, no tiny handwriting.

If you want a full, tool by tool walk through of label types, printers and layout, the Trainar Academy piece How To Set Up Van Stock Control With Barcodes Printers Labels And A 60 Minute Setup is worth twenty minutes of your time.

Wire Google Sheets into WhatsApp for automatic low stock alerts

Once the sheet and labels work in the field, the real win is automation: sending a WhatsApp alert when stock falls below a sensible minimum.

You have two main options.

No code: Zapier or Make

Tools like Zapier and Make.com give you a graphical way to connect Google Sheets and the WhatsApp Business Cloud API.

The flow looks like this:

1. Trigger whenever a row in your van sheet changes or a quantity goes below the minimum threshold.
2. Action sends a WhatsApp message via your connected WhatsApp Business Cloud API number to the relevant engineer or office manager.

You will need:

• A Meta developer account and WhatsApp Business Cloud API setup
• At least one approved message template for business initiated alerts
• A Zapier or Make account with access to both Google Sheets and WhatsApp integrations

To see the mechanics step by step, watch How To Send WhatsApp Notifications From Google Sheets Using Zapier on YouTube:

The video walks through the exact pattern you need; you can adjust the wording to something like:

Low stock: Copper 15mm Tee (SKU 345123) on Van 2. Only 3 left on shelf B2. Reply YES when you have collected from merchant.

For small teams, most alerts will fall inside the 24 hour reply window, so you stay on the free side of Meta pricing. Template driven broadcasts to a long inactive contact list are where charges kick in.

Low cost code: Google Apps Script

If you prefer to avoid third party automation tools, Google Apps Script lets you attach logic directly to your sheet.

Typical pattern:

• A simple function runs on edit or as a time based trigger.
• When it finds any SKU where qty < minimum, it fires an HTTP POST to the WhatsApp Cloud API /messages endpoint with the payload for a 1 to 1 message.

This route is more technical but has zero extra subscription cost. The official WhatsApp Cloud API documentation gives clear examples of the payload structure.

Whichever route you choose, respect one important limitation: the official API does not support sending to WhatsApp Groups. All alerts must be 1 to 1, otherwise you risk your number being blocked.

Make WhatsApp photos part of your audit trail, not just the chat scroll

In 2026, WhatsApp’s default photo compression is still a problem for evidence. For anything you might rely on with insurers, main contractors or HMRC, you want full resolution.

Train your teams to:

• Send important photos as HD or as a document so resolution is preserved
• Include job reference, van and rough location in the message or file name

From there, use Zapier or Make again: hook a WhatsApp webhook from the Cloud API into a flow that saves incoming media to Google Drive or SharePoint, dropping them into folders by job or van. That gives you a proper archive and makes it much easier to hit record keeping requirements.

For more depth, see the Trainar Academy article Autofile WhatsApp Photos Straight Into Google Drive Job Folders No Faff, which breaks down folder structures and retention policies in more detail.

Compliance: keep HMRC and ICO off your back

Any system that touches staff details, client addresses or job photos needs to respect UK GDPR. The Information Commissioner’s Office has a clear overview of the storage limitation principle on its site, which essentially says: do not keep data longer than needed and know where it lives.

For financial and tax records, HMRC expects:

• Self employed: keep records for at least five years after the 31 January submission deadline for the relevant tax year, as set out in GOV.UK guidance
• VAT registered: keep digital or paper VAT records for at least six years, under GOV.UK VAT record rules

From April 2026, Making Tax Digital for Income Tax goes live for individuals with income above £50,000, then above £30,000 from 2027, according to official HMRC guidance. That will increase the pressure on small firms to have clean, digital records, not random photos buried in WhatsApp chats.

Your WhatsApp and Sheets workflow can help if you:

• Move important messages and photos into structured Drive or SharePoint folders
• Apply simple retention rules, deleting or archiving anything you no longer need once statutory periods pass
• Avoid sending bulk WhatsApp messages in ways that breach Meta’s business terms

If you want to stress test your setup, communities like /r/uktrades and /r/automation often share real world patterns for logs, backups and retention.

When to graduate from DIY to a paid platform

The Google Sheets plus WhatsApp model is brilliant for:

• One to five vans
• Under about 200 active SKUs
• Teams happy to tweak a bit of logic now and again

It starts to strain when you need:

• Automated purchase orders to preferred suppliers
• Live job costing, forecasting and profitability per project
• Certificates, forms and asset histories tied automatically to jobs

At that point, tools like Tradify, Joblogic, Commusoft and ServiceM8 earn their licence fee. They centralise jobs, stock, POs and financials in a way that a sheet never will.

A sensible path is to run DIY for a year while you stabilise van stock and WhatsApp workflows, then graduate to a platform that either ingests your sheet data or integrates directly with your accounting platform. The Trainar Academy guide Build A Live Job Margin Workflow Tradify To Xero Or QuickBooks Without Double Entry is a good read before you make that jump.

If you want to compare out of the box inventory options before committing, this YouTube review of Top 5 Free Inventory Management Software For Small Business (2025) is a strong overview:

FAQs

Can I send WhatsApp alerts to my whole site team automatically?
Not via the official Cloud API. It supports 1 to 1 messages only. You can still have a normal WhatsApp Group and manually forward key alerts into it, but do not try to automate group or broadcast sends through unofficial tools or you risk suspension.

Is barcode hardware really necessary, or can I just type into the sheet?
You can type, but adoption falls off quickly. In practice, a few rugged labels and the phone camera as a scanner are enough to make updating almost effortless, which is what keeps the system alive after the first month.

What if engineers forget to update the sheet when they take stock?
Expect some drift. The trick is weekly or fortnightly mini audits, where the engineer scans each shelf and does a five minute check. Combine that with low stock alerts and you will still be miles ahead of the “guess and hope” system.

How much will WhatsApp Business Cloud API actually cost me?
For day to day service messages inside an existing 24 hour chat window, Meta currently charges nothing. Template based business initiated messages are billed per message. UK pricing can change, so always check your BSP or Meta’s latest rate card before you send large volumes.

Can this help with MTD and HMRC inspections, or is it just convenience?
If you archive WhatsApp evidence into structured folders, tie them to jobs and keep them for the correct duration, it absolutely supports Making Tax Digital and HMRC reviews. The key is that your records are accessible, complete and not silently deleted when someone changes phone.

Want to slash training times and increase revenue per Engineer? Join our Waitlist: https://trainar.ai/waitlist

Training and resources

Official guidance and standards

• UK GDPR storage limitation principle overview – ICO
• Record keeping for the self employed – GOV.UK
• VAT record keeping rules – GOV.UK
• Making Tax Digital for Income Tax introduction – GOV.UK
• WhatsApp Business Cloud API documentation – Meta developer docs

Tools and suppliers mentioned

• Tradify pricing – tradifyhq.com
• Joblogic – joblogic.com
• Commusoft pricing – commusoft.co.uk
• ServiceM8 UK pricing – servicem8.com
• Zoho Inventory – zoho.com
• Sortly – sortly.com
• Odoo – odoo.com
• Katana – katanamrp.com
• Zapier WhatsApp integrations – zapier.com
• The Barcode Warehouse – thebarcodewarehouse.co.uk
• Labelzone Zebra labels – labelzone.co.uk
• AA Labels – aalabels.com

Further learning and community support

• Autofile WhatsApp Photos Straight Into Google Drive Job Folders No Faff – Trainar Academy
• How To Set Up Van Stock Control With Barcodes Printers Labels And A 60 Minute Setup – Trainar Academy
• Build A Live Job Margin Workflow Tradify To Xero Or QuickBooks Without Double Entry – Trainar Academy
• Reddit UK trades community – /r/uktrades
• Reddit automation community – /r/automation
• Top 5 Free Inventory Management Software For Small Business (2025) – YouTube
• How To Send WhatsApp Notifications From Google Sheets Using Zapier? – YouTube