A service invoice register does not show every required input detail
Rule 56(13) requires every registered person supplying services to maintain accounts showing quantitative details of goods used in providing services, details of input services utilised and services supplied. A consultancy or repair business should therefore retain more than its final customer invoices. The precise information should reflect its actual service process. ICAI April 2026 statutory compilation: CGST Rule 56(13), (15) and (16).
Do not import the manufacturing rule’s wording
Sub-rule (12) separately requires monthly manufacturing production accounts. Sub-rule (13) addresses service providers and does not itself prescribe a universal manufacturing yield, machine-hour unit or monthly production format for them. Its express quantitative-goods requirement should be distinguished from details of input services and outward services. Monthly management reconciliations can be useful controls without being presented as a new statutory format.
Separate purchases, use, assets and service delivery
Goods purchased may remain unused, be returned, be capital equipment or be consumed in customer work. Preserve descriptions, units and usage evidence rather than treating every invoice as current consumption. Input services can support several assignments; retain a rational, evidenced allocation where needed. Time sheets, job cards, service completion records and contract milestones can explain supplied services without asserting one universal legal measure.
Records do not settle substantive tax treatment
A consumption allocation does not by itself prove ITC eligibility, classification, valuation or time of supply. Works contracts can require the additional separate-account particulars under sub-rule (14). Electronic authentication, preservation and access follow the other applicable provisions, including sub-rules (15)–(16). Examples below are operational reconciliations for service businesses; model units and allocation ratios are not statutory tolerances.
Applicable primary references
ICAI April 2026 statutory compilation: CGST Rule 56(13), (15) and (16)
Six worked illustrations
All facts and amounts below are fictional. Assumptions describe the model, not additional statutory rules.
Illustrative example 1: Consumable use
A repair service opens with 100 metres of cable, receives 300 and closes with 80, with no returns or other movements. Model usage is 320 metres. Purchase quantity alone would understate that usage by 20 metres.
Illustrative example 2: Unused kits
A service business purchases fifty identical consumable kits and uses thirty-five in completed jobs. Fifteen remain unused. Treating all fifty as used overstates consumption by fifteen kits.
Illustrative example 3: Shared input service
An evidenced ₹60,000 input service supports jobs A and B on a supported 2:1 basis. Internal allocations are ₹40,000 and ₹20,000. The ratio is not prescribed by GST law, and the allocation does not itself decide ITC.
Illustrative example 4: Returns reconciliation
A service team receives twenty replacement modules and returns four unused. Sixteen remain available in the model. If twelve are used, four remain unused; preserve both supplier-return and usage records.
Illustrative example 5: Hours and job evidence
Time records show 200 hours, comprising 150 on delivered assignments and fifty on unfinished work. Delivered-work share is 75%. That ratio is a control metric, not an automatic revenue, invoice or GST time-of-supply rule.
Illustrative example 6: Invoice versus job duplication
Ten completed jobs have one job record each, but two jobs are accidentally listed twice in an extract. The extract contains twelve rows but only ten distinct jobs. Reconcile the two duplicate rows rather than treating the row count as twelve supplied jobs.
Ten-step verification table
| Step | Action | Evidence |
|---|---|---|
| 1 | Identify service activities | Actual business and registered-person scope. |
| 2 | Map goods used | Descriptions and meaningful quantity units. |
| 3 | Bridge consumables | Opening, receipts, returns, use and closing. |
| 4 | Separate equipment | Do not call every purchase consumption. |
| 5 | Trace input services | Invoices and actual utilisation. |
| 6 | Support allocations | Documented basis across assignments. |
| 7 | Trace outward services | Contracts, job cards and completion evidence. |
| 8 | Resolve duplicates | Unique job and invoice references. |
| 9 | Review tax separately | ITC, value and supply timing. |
| 10 | Preserve records | Authentication, supporting documents and access. |
Sixteen practitioner FAQs
1. Who falls under sub-rule (13)?
Every registered person supplying services on its terms.
2. Is an outward invoice list alone sufficient?
It may omit the required input and consumption evidence.
3. Which goods information is expressly quantitative?
Goods used in providing services.
4. Are input services addressed?
Yes. Maintain details of services utilised.
5. Are outward services addressed too?
Yes. Maintain details of services supplied.
6. Does this paragraph prescribe manufacturing yields?
No.
7. Does it itself specify one monthly production format?
No. Do not import sub-rule (12)’s manufacturing wording.
8. Can a monthly management review still help?
Yes, as an internal control.
9. Does buying a consumable prove it was used immediately?
No. Reconcile custody and use.
10. Should capital equipment be distinguished?
Yes. Avoid treating all purchases as current consumption.
11. Is 2:1 a statutory service-allocation ratio?
No. It is an evidenced model assumption.
12. Can time sheets support service evidence?
They can support actual facts without becoming a universal statutory unit.
13. Does an allocation itself prove ITC eligibility?
No. Check substantive credit requirements separately.
14. Can works contracts require more particulars?
Yes. Review sub-rule (14) where applicable.
15. Does a delivered-hours percentage fix time of supply?
No. Apply the relevant supply and invoicing provisions.
16. What is the strongest closing evidence?
A source-linked input-use and service-delivery reconciliation with duplicates and differences resolved.
Conclusion
Service providers need records of goods used, input services utilised and services supplied. Reconcile consumption and delivery evidence without importing manufacturing yield rules.