What is a workshop job card, and why does the format matter?
A job card is the record of one vehicle visit. It follows the car from the gate to the invoice.
Most garages already keep one. The trouble is that the card and the bill are kept in different places. The card lives on paper at the service bay. The bill is typed up afterwards from memory and a pile of parts slips. Anything the card did not capture has to be reconstructed, and reconstruction is where the margin quietly leaks.
A good format closes that gap. Every line that will appear on the invoice already exists on the card, with the tax treatment attached to it.
Which columns does an automobile job card need?
Group the card into five blocks. Each one answers a question that comes up later.
1. Vehicle and customer block
Registration number, make and model, chassis or VIN, odometer reading at entry, fuel level, and the owner's name, phone and GSTIN if they have one.
The odometer reading matters more than it looks. It fixes when the service happened in the vehicle's life, which is what a warranty claim or a next-service reminder is calculated from.
Capture the customer's GSTIN when they are a business. A fleet operator or a company car cannot claim input tax credit on the repair without it, and they will ask you to reissue the invoice if you leave it off.
2. Complaint, findings and cause
Three separate fields, not one.
The complaint is what the customer said. The finding is what the technician saw. The cause is why it happened. Keeping them apart is what lets you show a customer that the noise they reported and the worn bush you replaced are the same problem.
3. Parts issued
Part number, description, HSN code, quantity, unit rate, discount, taxable value, GST rate and tax amount.
Parts are goods. Most motor vehicle parts sit under HSN heading 8708, but the rate is not uniform across every item a workshop stocks, and it has changed more than once. Confirm the current rate for the specific part rather than hard-coding one into your template. Both the HSN code finder and the CBIC rate finder both do this.
4. Labour performed
Operation description, technician name, standard hours, actual hours, rate per hour, taxable value, GST rate and tax amount.
Maintenance and repair of motor vehicles is a service, and it falls under SAC 998714. That code belongs on the labour lines and nowhere else.
Recording standard hours next to actual hours is worth the extra column. Over a few months it tells you which jobs your quoting is wrong about.
5. Approvals and handover
Estimate given, estimate approved by, date and time of approval, revised estimate if any, and the same again for the revision. Then delivery date, final odometer and the customer's signature at handover.
How should parts and labour be billed under GST?
On separate lines, with their own codes.
This is the part garages most often get wrong. A single line reading "Service charges — Rs 8,400" hides two different supplies with two different tax treatments inside one figure. If the rate on the parts differs from the 18% on labour, and it usually does, that merged line cannot be right.
| Spare parts | Labour | |
|---|---|---|
| Nature of supply | Goods | Service |
| Code on the invoice | HSN, commonly 8708 for vehicle parts | SAC 998714 |
| Rate | Varies by part; verify per item | 18% |
| Stock effect | Reduces inventory | None |
| Margin driver | Purchase price vs selling price | Hours billed vs hours paid |
Because the two behave differently, they need to be measured differently too. Parts margin is a buying question. Labour margin is a scheduling question. Our job card margin calculator splits a single job into both so you can see which half actually earned the money.
A worked example
A brake job: pads at Rs 3,200 and a disc at Rs 4,600, both taxed at 28%, plus 2.5 hours of labour at Rs 600 an hour taxed at 18%.
| Line | Code | Taxable value | Rate | Tax | Total |
|---|---|---|---|---|---|
| Parts | HSN 8708 | Rs 7,800 | 28% | Rs 2,184 | Rs 9,984 |
| Labour | SAC 998714 | Rs 1,500 | 18% | Rs 270 | Rs 1,770 |
| Invoice | Rs 9,300 | Rs 2,454 | Rs 11,754 |
Merge those into one line at 18% and the tax collected falls to Rs 1,674. That is a shortfall of Rs 780 on a single brake job, and it is your liability, not the customer's. Rates differ by part, so treat 28% here as an illustration and confirm the figure for what you actually fitted.
Excel or Word: which format should a workshop use?
Use both, for different jobs.
Excel for anything that is counted. Parts lines, hours, tax columns and totals all benefit from formulas, and you can total a month of cards without retyping anything. If you only keep one, keep this one.
Word for the printed card that goes to the service bay and comes back with a signature. It prints predictably and it is easier for a service advisor to fill by hand.
The practical setup in most garages is an Excel workbook as the record and a Word print-out as the physical trail.
What does the approval trail actually protect you from?
The bill the customer did not expect.
Almost every disputed invoice at a garage comes down to the same sequence. The car came in for one thing, a second fault was found, the work was done because the bay was free and the part was on the shelf, and nobody told the owner until they arrived to collect it.
The fix is procedural, not technical. Record the estimate before work starts. When the figure moves, record the revision, who approved it, and when. A time-stamped approval, even a WhatsApp message pasted into the card, turns an argument into a document.
It matters commercially too. A service is a supply to a consumer, and a consumer who was billed for work they never authorised has a straightforward complaint to make. The cheapest place to settle that is before the work starts.
When does a paper job card stop being enough?
Three signs, usually in this order.
You cannot answer questions about last month. Which technician is slowest on brake jobs? Which part sells at the worst margin? Paper holds the data but will not aggregate it.
Parts stock stops reconciling. Issue slips get written up after the fact, and the shelf count and the book count drift apart.
E-invoicing becomes mandatory. Once aggregate turnover crosses Rs 5 crore, invoices have to be reported to the Invoice Registration Portal and carry an IRN and QR code, as set out on the GST e-invoice portal. That cannot be done from a paper card. This threshold has stepped down repeatedly, so check where it stands before assuming you are outside it.
None of these mean you should abandon the card. They mean the card should live somewhere that can count.
A job card format you can copy
Lay the sheet out in this order and it will carry a job from gate to invoice without anything being retyped:
- Header: job card number, date in, promised delivery date, service advisor.
- Vehicle: registration, make, model, VIN, odometer in, fuel level.
- Customer: name, phone, address, GSTIN.
- Complaint / finding / cause: three columns, one row per issue.
- Parts: part no., description, HSN, qty, rate, discount, taxable value, GST %, tax, total.
- Labour: operation, technician, standard hrs, actual hrs, rate, taxable value, SAC 998714, GST %, tax, total.
- Summary: parts subtotal, labour subtotal, taxable value, CGST, SGST or IGST, round-off, grand total.
- Approvals: estimate, approved by, timestamp; revision, approved by, timestamp.
- Handover: delivery date, odometer out, customer signature.
Keep CGST and SGST as two columns rather than one combined figure. For a customer in another state you will need IGST instead, and a template that assumes intra-state supply will quietly produce a wrong invoice the first time you serve one.
Where to go next
If you are setting up billing from scratch, work out the margin question before the format question — the job card margin calculator shows what a job earns once parts, labour and discount are separated. For the tax side, the HSN code finder settles the code for a specific part, and the GST calculator handles the inclusive and exclusive arithmetic.
Workshops moving off spreadsheets entirely usually do it when stock reconciliation breaks, not when billing does. That is the point at which the card needs to be part of a system rather than a document.