An apparently small Unit of Measurement (UOM) mistake in an e-Way Bill can become a significant problem when goods are intercepted during transportation.

Consider a practical situation where a customer orders a composite item consisting of two components forming one complete set. The Purchase Order describes both components together in a single item description and places an order for 50 units of that composite item.

The supplier prepares the tax invoice according to the Purchase Order. The description, quantity, HSN, taxable value and GST are correct.

However, while generating the e-Way Bill, the UOM is inadvertently transmitted or selected as “NOS” rather than the unit intended to represent the composite set.

The vehicle is subsequently intercepted by a GST officer.

The officer notices the UOM issue and questions whether the goods being transported correspond to the invoice and e-Way Bill.

What appears to the accounting department to be a simple data-entry or UOM-mapping mistake can therefore become a GST compliance issue during movement of goods.

This case study explains how such a situation should be understood, documented and handled.

Privacy Note: All company names, GSTINs, PO numbers, invoice numbers, e-Way Bill numbers, addresses, vehicle numbers, transporter details, rates and other identifying particulars in this case study have been changed or generalized. The case is presented solely for educational purposes.

1. Background of the Case

A manufacturing supplier received a Purchase Order from a corporate customer.

The customer required a fabricated assembly consisting broadly of:

Component A + Component B

Both components together constituted the commercially supplied composite item.

Instead of issuing two independent PO lines, the customer issued one PO line containing the combined description.

For illustration:

Item Description:
“Supply of Component A + Component B, complete assembly as per approved drawing/specification.”

Quantity: 50
UOM: Each
Rate: ₹10,000 per composite item
Taxable Value: ₹5,00,000
GST: As applicable

Therefore, commercially, the transaction was not:

50 Component A only

or

50 Component B only.

It was for:

50 complete composite items, with Component A + Component B forming each supplied unit/set.

This distinction became important later.

2. What the Purchase Order Established

The Purchase Order was an important document for establishing the commercial substance of the transaction.

In the actual case that inspired this anonymized study, the customer's PO contained a single item line, a composite description containing the relevant components, quantity 50, UOM “Each”, one rate and one total value.

The PO also calculated the GST and overall order value on that same single line.

This is important because the PO can help establish what the customer actually ordered.

The commercial interpretation is therefore based not merely on the word “Each”, but on the entire item description read together with the quantity, rate and PO line structure.

3. How the Invoice Was Prepared

The supplier subsequently raised its tax invoice against the Purchase Order.

The invoice broadly followed the same structure:

Description: Component A + Component B forming the complete supplied item
Quantity: 50
UOM: Each
HSN: Correct HSN
Rate: Same contractual rate
Taxable Value: Matching PO value
GST: Correctly calculated
Total Invoice Value: Correct

Therefore, the invoice did not split the components into separate commercial supplies.

There was one composite description corresponding to the customer's PO.

4. Where the Problem Occurred

The accounting team generated the e-Way Bill through its accounting/e-Way Bill workflow.

During this process, the UOM appearing in the generated e-Way Bill became:

50 NOS

rather than the unit intended to communicate the composite nature of the supply.

This was the key discrepancy.

The problem was not necessarily the numeric quantity “50.”

The problem was the interpretation that could arise from:

50 NOS

when the underlying commercial documents described 50 composite items containing multiple components.

5. Why a Small UOM Error Can Become Important

An accountant familiar with the transaction may immediately understand what “50” represents.

A GST officer intercepting a vehicle does not necessarily have that background.

The officer has to compare documents and physical goods.

Suppose the officer sees:

Purchase Order: 50 Each of Component A + Component B
Invoice: 50 Each of the composite description
E-Way Bill: 50 NOS
Physical vehicle: Components corresponding to 50 complete assemblies

The officer may ask:

• What exactly does 50 NOS mean?
• Are there 50 individual pieces or 50 complete sets?
• Why does the physical consignment contain multiple components?
• Does the e-Way Bill accurately describe the goods?
• Is the quantity understated?
• Is there any unaccounted material?
• Does the invoice correspond to the goods physically carried?

These questions demonstrate why UOM selection should never be treated as an insignificant field during e-Way Bill preparation.

6. “Each”, “NOS”, “PCS” and “SETS” Should Not Be Used Carelessly

Different commercial systems use terms such as:

Each – each commercially supplied unit
NOS – numbers
PCS – pieces
SET – sets
UNT – units

The official e-Way Bill master-code documentation contains standardized quantity-unit codes, including PCS for Pieces, SET for Sets and UNT for Units.

This becomes particularly important where one commercially supplied item consists of multiple physical components.

For example:

1 Set = 1 Frame + 4 Clamps + 8 Fasteners

If the order is for 50 sets, the vehicle may physically contain:

50 Frames
200 Clamps
400 Fasteners

Yet commercially, the transaction can still represent:

50 Sets

provided that this is genuinely how the underlying supply, PO, invoice and applicable documentation are structured.

The physical count of individual components should therefore not automatically be confused with the commercial quantity of the composite item.

7. Was This Automatically a Case of Tax Evasion?

Not necessarily.

A discrepancy in an e-Way Bill requires examination of the actual facts.

Important questions include:

Was the supplier genuine?

Was the recipient genuine?

Was there a genuine Purchase Order?

Was a valid tax invoice issued?

Was the correct HSN disclosed?

Was the taxable value fully disclosed?

Was GST calculated on the full taxable value?

Was the numeric commercial quantity consistent?

Were the goods physically being supplied against the stated transaction?

Was there any excess/unaccounted material?

Did the discrepancy result in suppression of taxable value or tax?

These facts can be highly relevant when explaining why a UOM discrepancy was a bona fide mistake rather than an attempt to conceal a different transaction.

However, businesses should avoid assuming that merely calling something a “clerical error” automatically removes all possible consequences. The Proper Officer must consider the facts and applicable law.

8. CBIC Guidance on Minor E-Way Bill Discrepancies

CBIC issued Circular No. 64/38/2018-GST dated 14 September 2018 dealing with interception of conveyances and discrepancies in e-Way Bills.

The Circular records that representations had been received concerning penalties for minor discrepancies in e-Way Bill details where there were no major lapses in the accompanying invoices.

This is an important compliance principle.

However, there is an equally important caution:

A wrong UOM should not automatically be claimed as one of the specifically listed minor-error categories under this Circular.

The Circular identifies particular circumstances. A UOM discrepancy is not expressly listed merely because it appears clerical.

Therefore, a taxpayer should avoid making an absolute statement such as:

“Wrong UOM is specifically exempted under Circular 64/38/2018.”

That could overstate what the Circular actually says.

A more defensible approach is:

The discrepancy is bona fide and clerical in nature; the substantive documents, quantity/value/tax trail and physical goods should be examined, and the principles concerning treatment of minor discrepancies may be considered according to the facts and applicable law.

9. Why the Document Trail Matters

One of the strongest protections in such a situation is a clear documentary chain:

Purchase Order → Tax Invoice → e-Way Bill → Transport Document → Physical Goods

Each should be compared.

Purchase Order

Establishes what the customer ordered.

Tax Invoice

Establishes what the supplier invoiced.

E-Way Bill

Provides prescribed information for movement of goods.

Transport Document

Links the consignment with the transporter/vehicle.

Physical Goods

Should correspond to the commercial transaction reflected in the documents.

When these documents substantially tell the same commercial story, it becomes easier to explain an isolated UOM discrepancy.

10. Important Evidence in This Type of Case

The business should immediately collect and preserve:

1. Original Purchase Order
2. Tax Invoice
3. E-Way Bill
4. Delivery challan, if applicable
5. Transporter's LR/GR/bilty
6. Product drawing/specification
7. Packing list
8. Customer correspondence concerning the order
9. Accounting-system records
10. Stock records
11. E-invoice/IRN details, where applicable
12. Evidence showing how the composite item is normally supplied
13. Photographs of goods, where useful
14. Written clarification from the customer, if obtainable

A customer confirmation can be especially helpful where terminology is ambiguous.

For example, the customer may confirm that:

The PO quantity represents 50 complete composite items and that the components mentioned in the description together constitute each ordered item.

Such confirmation should, of course, reflect the genuine commercial arrangement and not be created merely to change facts after interception.

11. Do Not Blame Accounting Software Without Evidence

A common reaction is to write:

“Tally automatically made this mistake.”

That statement should be avoided unless it can actually be demonstrated.

The discrepancy might have arisen from:

• incorrect stock-item UOM;
• incorrect mapping;
• manual selection;
• master configuration;
• API mapping;
• operator error;
• data conversion;
• integration configuration;
• incorrect JSON generation; or
• another accounting workflow.

The e-Way Bill API itself includes a qtyUnit field for the unit associated with the product quantity.

Therefore, the safer description is:

“An inadvertent clerical/data-entry/UOM-mapping discrepancy occurred during preparation or generation of the e-Way Bill through the accounting/e-Way Bill system.”

This acknowledges the error without making an unsupported technical allegation against the software.

12. Can an Incorrect E-Way Bill Simply Be Edited?

Generally, no.

The official e-Way Bill FAQ states that after an incorrect entry has been submitted, the e-Way Bill cannot simply be edited or corrected. The prescribed approach is cancellation and generation of a fresh e-Way Bill with correct details.

The FAQ also states that an e-Way Bill generated with wrong information can be cancelled and generated afresh, subject to the applicable cancellation conditions and time limit.

The official cancellation documentation states that cancellation can be done by the generator and generally within 24 hours of generation.

There is another very important limitation.

The official FAQ says that where the e-Way Bill has been verified by the Proper Officer, it cannot be cancelled.

Therefore, once a vehicle has already been intercepted, businesses should not casually attempt cancellation/regeneration without checking the status and obtaining professional advice appropriate to the case.

13. What Should the Driver Do When the Vehicle Is Intercepted?

The driver should remain cooperative and avoid making speculative explanations.

The driver should produce the available prescribed and supporting documents.

If the driver does not understand the accounting issue, he should not attempt to interpret the PO.

A practical response is:

“The documents have been generated by our accounts department. Kindly allow me to connect you with the authorized accounts/GST representative for clarification.”

The accountant, tax professional or authorized representative can then explain the commercial structure with the documents.

14. How the Business Should Explain the UOM Discrepancy

The explanation should focus on verifiable facts.

For example:

“The customer placed one PO line for a composite item consisting of Component A + Component B. The PO quantity is 50 and both components are contained in the same item description. The invoice follows the same commercial description and quantity. During e-Way Bill preparation, the UOM was inadvertently represented as NOS. There was no intention to change the goods, quantity, taxable value or GST liability.”

Then show the documents.

Avoid emotional arguments.

Avoid accusing the GST officer.

Avoid saying:

“It is only a small mistake, so you cannot stop us.”

Instead, demonstrate why the discrepancy does not alter the underlying transaction.

15. A Useful Reconciliation Table

Particular	Purchase Order	Tax Invoice	E-Way Bill
Supplier	Matching	Matching	Matching
Recipient	Matching	Matching	Matching
Item	Composite description	Composite description	Corresponding goods
Quantity	50	50	50
HSN	Correct	Correct	Correct
Taxable Value	Matching	Matching	Matching
GST	Matching	Matching	Matching
Total Value	Matching	Matching	Matching
UOM	Each	Each	NOS – discrepancy

This table makes the issue immediately understandable.

Instead of allowing the entire transaction to appear questionable, it isolates the problem:

The disputed field is the UOM terminology, while the other material commercial particulars reconcile.

16. Why Correct Taxable Value Is Important

Suppose the transaction is:

50 composite items × ₹10,000 = ₹5,00,000

and GST is correctly calculated on ₹5,00,000.

If the e-Way Bill also reports the same taxable amount, then a UOM discrepancy has not, by itself, reduced the taxable value.

That is relevant when explaining absence of tax suppression.

However, correct tax payment does not mean businesses can ignore e-Way Bill accuracy. The prescribed particulars should still be correctly furnished.

17. What If Physical Components Are More Than the Number Written in the E-Way Bill?

This requires careful explanation.

Suppose:

1 Set = 2 physical components

and the supply is:

50 Sets

The vehicle may contain 100 component pieces.

This does not automatically mean the commercial quantity must be entered as 100, provided the actual supply is genuinely structured and documented as 50 sets.

But the documents should make this relationship clear.

Ambiguous descriptions increase interception risk.

A better description would be:

“Complete Assembly – 1 Set comprising Component A (1 No.) + Component B (1 No.)”

Quantity:

50 SET

This is much clearer than simply listing two component names and writing “50 NOS.”

18. Prevention: Improve the Item Description

Accounting teams should make composite-product descriptions self-explanatory.

Instead of:

Template + Anchor Plate

consider:

“Template & Anchor Plate Complete Set – 1 Set comprises 1 Template + 1 Anchor Plate.”

Then use:

Quantity: 50 SET

where that accurately reflects the customer's order and the actual commercial transaction.

This substantially reduces interpretational disputes.

19. Configure Stock Masters Carefully

If e-Way Bills are generated through accounting software, review the stock-item master before dispatch.

Verify:

Stock Item Name
HSN/SAC
GST Rate
Primary UOM
Alternate UOM
Quantity
Item Description
E-Invoice mapping
E-Way Bill mapping

Do not assume that the printed invoice and electronically transmitted e-Way Bill will always use identical UOM terminology.

20. Create a Pre-Dispatch E-Way Bill Verification Process

For high-value consignments, the e-Way Bill should be checked independently before the vehicle leaves.

A recommended workflow is:

Step 1: Prepare invoice.

Step 2: Generate e-Invoice/IRN where applicable.

Step 3: Generate e-Way Bill.

Step 4: Download/print the final e-Way Bill.

Step 5: Compare it with the PO and invoice.

Step 6: Verify supplier and recipient GSTIN.

Step 7: Verify document number and date.

Step 8: Verify HSN.

Step 9: Verify quantity.

Step 10: Verify UOM.

Step 11: Verify taxable value and GST.

Step 12: Verify vehicle/transporter details.

Step 13: Release the vehicle only after verification.

A two-person verification procedure can be particularly useful for high-value dispatches.

21. What If the Error Is Discovered Before the Vehicle Leaves?

Do not ignore it merely because the value and tax are correct.

If an e-Way Bill contains incorrect information, examine whether cancellation and fresh generation are required.

The official e-Way Bill guidance says that an incorrect e-Way Bill cannot simply be edited after generation; where permitted, it must be cancelled and generated afresh with the correct information.

Correcting the problem before dispatch is significantly easier than explaining it during roadside interception.

22. What If the Error Is Found During Transit?

Immediately involve:

• Accounts department
• GST/compliance team
• Authorized company representative
• CA/GST practitioner, where necessary
• Customer, if confirmation is required

Prepare a written reconciliation.

Do not fabricate or alter supporting documents retrospectively.

The objective should be to demonstrate the genuine transaction exactly as it occurred.

23. What If the Vehicle Has Already Been Intercepted?

This is more sensitive.

Once the Proper Officer has begun verification, do not assume that cancelling the e-Way Bill will solve the problem.

The official e-Way Bill FAQ specifically states that an e-Way Bill which has been verified by the Proper Officer cannot be cancelled.

The taxpayer should therefore obtain case-specific professional advice and respond to the officer with the underlying documents and factual explanation.

24. Key Lessons from This Case

This case provides several useful lessons for accounting and GST teams.

Lesson 1 – UOM is not a cosmetic field

Incorrect UOM can change how the physical quantity is interpreted.

Lesson 2 – Composite products need clear descriptions

If multiple components constitute one set, say so explicitly.

Lesson 3 – PO terminology matters

Accounts teams should understand how the customer's PO defines the commercial item before creating masters and invoices.

Lesson 4 – Invoice and e-Way Bill should be reconciled

Do not verify only value and GST.

Verify quantity and UOM too.

Lesson 5 – Avoid unsupported explanations

Do not automatically blame Tally, ERP software, the GST portal or an API.

Determine what actually happened.

Lesson 6 – Preserve evidence

PO, invoice, packing list, transport documents, drawings and correspondence can become crucial during an interception.

Lesson 7 – Correct mistakes before dispatch

A five-minute verification before vehicle release can prevent hours of detention and compliance work.

25. Frequently Asked Questions (FAQ)

FAQ 1: What happens if the UOM is wrong in an e-Way Bill?

It can create a discrepancy between the e-Way Bill, invoice and physical goods. The seriousness depends on the facts, including whether the quantity, goods, taxable value and tax remain properly documented.

FAQ 2: Can an e-Way Bill be edited after generation?

Generally, the generated e-Way Bill cannot simply be edited. The official FAQ states that an incorrect e-Way Bill may need to be cancelled and generated afresh, subject to applicable conditions.

FAQ 3: How much time is available for cancellation?

Official e-Way Bill guidance generally provides a 24-hour cancellation window, subject to applicable conditions.

FAQ 4: Can an e-Way Bill be cancelled after a GST officer has verified it?

The official FAQ states that if the e-Way Bill has been verified by the Proper Officer, it cannot be cancelled.

FAQ 5: Is “SET” an official e-Way Bill unit code?

Yes. The official master-code list includes SET – SETS. It also includes PCS – PIECES and UNT – UNITS.

FAQ 6: If two components form one set, should quantity be two or one?

It depends on the genuine commercial structure of the supply and its documentation.

If the customer genuinely orders one complete set comprising two components and the invoice documents one set, the commercial quantity may be one set. The documentation should make the composition unambiguous.

FAQ 7: If 50 sets contain 100 physical components, does that automatically mean the e-Way Bill quantity should be 100?

No universal conclusion should be drawn solely from the physical piece count. The correct quantity/UOM should correspond to the actual commercial supply and applicable e-Way Bill requirements. Clear item descriptions and packing details are important.

FAQ 8: Does wrong UOM automatically mean GST evasion?

No. Intent and liability cannot be concluded merely from the UOM field. The entire transaction and documents must be examined. At the same time, an incorrect UOM should not be ignored because it may constitute a compliance discrepancy.

FAQ 9: Does CBIC Circular 64/38/2018 specifically exempt every wrong-UOM case?

No. The Circular addresses minor discrepancies and lists specified situations, but a wrong UOM should not automatically be represented as expressly covered by every listed relaxation.

FAQ 10: What is the strongest evidence when explaining a genuine UOM error?

A consistent documentary trail:

Purchase Order + Invoice + e-Way Bill + transport documents + physical goods + packing/specification records.

FAQ 11: Should we say “Tally made the mistake”?

Only if technical evidence establishes that fact.

Otherwise use neutral wording such as:

“The discrepancy occurred inadvertently during data entry/UOM mapping while generating the e-Way Bill through the accounting system.”

FAQ 12: What should be done if the mistake is discovered before dispatch?

Stop the dispatch, verify the documents and follow the applicable process for cancelling/regenerating an incorrect e-Way Bill where required and permitted.

FAQ 13: What should the driver say to the GST officer?

The driver should produce the documents and connect the officer with the authorized accounts/GST representative rather than giving an uncertain technical explanation.

FAQ 14: Can a customer Purchase Order help during GST verification?

Yes. A genuine PO can provide important evidence regarding the item ordered, its description, quantity, UOM, rate and commercial structure.

FAQ 15: Should composite items be described as “SET”?

Where “set” accurately reflects the actual commercial supply, using an explicit description such as “1 Set comprising A + B” can make the documentation clearer. The UOM should remain consistent with the underlying transaction.

Conclusion

The central lesson from this case is simple:

A small data field can create a large compliance problem when goods are physically in transit.

Where a customer orders a composite product comprising multiple components under one PO line, the accounting and dispatch teams must ensure that the Purchase Order, Tax Invoice, e-Invoice, e-Way Bill, packing details and physical goods all communicate the same commercial transaction clearly.

If an e-Way Bill inadvertently shows NOS when the underlying transaction is structured around a composite set/unit, the business should not attempt to hide or casually dismiss the discrepancy.

Instead, it should establish the facts through documentation:

What did the customer order?
What was invoiced?
What is physically being transported?
What quantity was declared?
What UOM was intended?
Was the HSN correct?
Was the full taxable value disclosed?
Was the full GST liability disclosed?

Where the documentary trail demonstrates a genuine transaction and the discrepancy is confined to UOM terminology, those facts should be clearly placed before the Proper Officer.

Most importantly, businesses should prevent recurrence through a mandatory pre-dispatch verification of quantity and UOM, not merely GST amount and invoice value.

Disclaimer

This case study is provided strictly for educational and general informational purposes. Names, GSTINs, invoice numbers, Purchase Order numbers, e-Way Bill numbers, addresses, vehicle numbers, rates and other identifying details have been changed, anonymized or generalized.

GST law, rules, notifications, circulars, portal functionality and departmental interpretations may change. Treatment of an e-Way Bill discrepancy depends upon the specific facts and applicable law. This article should not be treated as legal, tax or professional advice. Before taking any action, responding to a GST notice, seeking release of detained goods/vehicle, paying a penalty, cancelling an e-Way Bill or making a representation before an authority, consult your practicing Chartered Accountant, GST practitioner, tax advocate or the concerned GST department. The publisher/author assumes no responsibility for any error, omission, loss, penalty or consequence arising from reliance on this educational article.

#Tags

#EWayBill #GST #GSTIndia #EWayBillError #WrongUOM #UOMError #GSTCompliance #GSTCaseStudy #GSTVehicleInterception #VehicleDetention #GSTOfficer #GSTInspection #GSTNotice #GSTPenalty #GSTClericalError #EWayBillMistake #EWayBillCorrection #EWayBillCancellation #EWayBillCompliance #GSTTransport #GoodsInTransit #GSTDocumentation #TaxInvoice #PurchaseOrder #InvoiceMismatch #EWayBillMismatch #CompositeItem #CompositeSupply #UnitOfMeasurement #SETS #NOS #PCS #GSTAccounting #TallyPrime #AccountingSoftware #GSTSoftware #GSTDataEntry #GSTBestPractices #GSTChecklist #DispatchChecklist #GSTDispatch #CBIC #CGST #CGSTRules #Section129GST #Rule138A #TaxCompliance #GSTFAQ #IndianGST #Knowledgebase