SRO 1666 of 2026: e-invoicing now covers federal excise and Islamabad services
On 29 September 2026, FBR issued two notifications that stretch the e-invoicing rules beyond sales tax. If you charge federal excise duty, provide services in Islamabad, or issue debit notes, credit notes or advance receipts, this is what changed.
Answer first. SRO 1666(I)/2026 amends Chapter XIV of the Sales Tax Rules, the chapter that holds the e-invoicing rules. Its companion, SRO 1667(I)/2026, adds a new rule 12A to the Federal Excise Rules. Together they apply the same e-invoicing system to federal excise duty and to Islamabad’s tax on services. A business already integrated for sales tax needs no second integration and no second integrator licence. One invoice can carry sales tax, excise and Islamabad services tax side by side. Debit notes, credit notes and advance receipt invoices must now be issued electronically and kept for six years. And an invoice with an FBR number that is missing from your return can now be taxed as an unaccounted sale.
What changed, rule by rule
| Rule | What it now says |
|---|---|
| Rule 150Q(4) and (5) | The Chapter XIV e-invoicing rules apply to persons required to issue e-invoices under the Federal Excise Act, and to providers of services taxed under the Islamabad Capital Territory (Tax on Services) Ordinance |
| Explanation to rule 150Q | A person already integrated under Chapter XIV does not need a separate technical integration for excise or Islamabad services tax |
| Rule 150R(13) | Six excise fields added to the invoice particulars |
| Rule 150S | Where sales tax, excise and services tax fall on the same transaction, one invoice with each tax shown separately is enough |
| Rule 150S, notes | Debit notes, credit notes and advance receipt invoices issued electronically and kept for six years |
| Licence rule | An integrator’s existing licence covers excise and Islamabad services tax; no separate licence |
| Rule 150XD(2) | Tax recovered on sales without an FBR-numbered invoice, and on FBR-numbered invoices left out of the return, unless lawfully cancelled |
| Federal Excise Rules, rule 12A (SRO 1667) | Chapter XIV applies to excise registrants who must issue FBR-numbered invoices; anyone integrated for sales tax counts as integrated for excise |
Both notifications are dated 29 September 2026. Neither sets a new deadline. They change what the system covers and what an invoice has to carry.
Who it affects
- Businesses that charge federal excise duty. Rule 12A of the Federal Excise Rules applies where a registered person must issue an invoice with an FBR number under section 18(5) of the Federal Excise Act. Most such businesses are also sales tax registered and already integrated, so the work is in their invoice data, not their connection.
- Service providers in Islamabad. Sales Tax General Order 05 of 2026 had already told service providers in Tables 1 and 2 of the ICT Ordinance to integrate. Their e-invoices were due from 15, 20 or 25 June 2026, by category. SRO 1666 writes the Chapter XIV rules for them into the Sales Tax Rules.
- Every integrated business that issues notes or takes advances. The electronic requirement for debit notes, credit notes and advance receipt invoices is general.
- Licensed integrators and software vendors. Their systems have to carry the new fields and keep each tax separately identifiable.
Services in Punjab, Sindh, Khyber Pakhtunkhwa and Balochistan are not affected. They are taxed by the provinces, through their own systems.
One invoice, three taxes
Before SRO 1666, it was unclear how to invoice a sale that carried both sales tax and excise. A new proviso to rule 150S settles it. Where sales tax, excise and Islamabad services tax fall on the same sale, one electronic invoice is enough. Each tax just has to be shown separately. Another new sub-rule adds that invoice data may include all three, securely transmitted and separately identifiable by tax type and mode.
A second proviso keeps the money side unchanged. How excise is charged, paid, adjusted and returned is still set by the Federal Excise Act. SRO 1666 changes the invoice, not the tax.
Audit also stays with each law. For a person brought in through the Federal Excise Act or the ICT Ordinance, a new sub-rule says audit and checks follow that law. FBR keeps the right to a technical audit of the shared e-invoicing system.
The new excise fields
Rule 150R(13) lists what an e-invoice must contain. SRO 1666 adds six excise particulars at the end of that list:
- Federal excise duty type
- Federal excise duty rate
- Price per unit for federal excise duty
- Federal excise duty amount, payable otherwise than in sales tax mode
- Federal excise duty SRO or Schedule reference
- Federal excise duty SRO or Schedule serial number
If you charge excise, these belong on your product list next to the HS code, sale type and sales tax rate. The pattern is familiar from sales tax: a reduced or special rate needs its SRO or Schedule reference, and the serial within it. Getting them onto each product once is far cheaper than typing them on every invoice.
Notes and advance receipts
An amendment to rule 150S says debit notes, credit notes and advance receipt invoices must also be issued electronically, and kept for six years. This sits alongside two Finance Act 2026 changes:
- Section 23(1) now requires an invoice for exempt supplies as well as taxable ones, including an advance receipt invoice, bearing a verifiable and unique FBR invoice number. The FBR-number part applies from a time the Board notifies. As at 1 October 2026 we have not found that notification, so treat it as coming rather than live.
- Section 9 now lets FBR prescribe the mechanism for debit and credit notes, including electronic adjustment.
In practice, stop issuing paper credit notes now. Then plan for advance receipts and exempt sales to go through the same system once FBR sets the date. A note still needs the FBR number of the original invoice, and the 180-day limit for notes is unchanged.
Invoices missing from your return
The substituted rule 150XD(2) is the part with the sharpest teeth. It applies where an integrated person either:
- makes sales without generating an invoice that carries an FBR number or QR code, or
- generates an invoice with an FBR number or QR code but leaves that supply out of Annexure-C or the sales declared in the return.
In either case, the officer computes the tax on the unaccounted sales or invoices and recovers it, on top of any penal action. The only exception is an invoice cancelled through a legally approved route, such as the 72-hour cancellation under Sales Tax General Order 01 of 2026.
Two everyday problems now carry a price. An accidental duplicate, sent twice because a reply was lost, is an FBR-numbered invoice for a sale that only happened once. And a test invoice sent to the live system by mistake is an FBR-numbered invoice for a sale that never happened. Both need cancelling inside the 72 hours, or they may be taxed as unaccounted sales. Compare your sales register with FBR’s record of your invoices before every return.
What has not changed yet
- The technical specification. FBR’s technical assistance page still links digital invoicing API version 1.12. We have not seen a published version with the excise fields. Expect one, but do not build to guesses about field names.
- Deadlines. Neither notification sets a date. The sales tax timetable in SRO 1852(I)/2025 is unchanged and all its dates have passed.
- Your integrator. No new licence or second enrolment is needed for excise or Islamabad services tax.
- Provincial services. PRA, SRB, KPRA and BRA systems are separate and unaffected.
What to do now
- Check whether you charge excise. If you do, ask your adviser whether section 18(5) of the Federal Excise Act requires FBR-numbered invoices for your goods or services.
- Add the excise fields to your product list. Type, rate, price per unit, SRO or Schedule reference and serial, for every item that carries excise.
- Ask your software vendor or integrator two questions. When will the excise fields be supported, and how will each tax be kept separate on one invoice?
- Move notes into the system. Debit and credit notes should already go through e-invoicing with the original FBR number.
- Reconcile before every return. Every FBR-numbered invoice should be in Annexure-C, or have been cancelled within 72 hours.
- Islamabad service providers: if you are not yet issuing e-invoices, your STGO 05 date has passed. Our catch-up plan is a good place to start.
Until FBR publishes the excise fields in its technical specification, your product list is the place to prepare.
FAQs
What is SRO 1666 of 2026? An FBR notification dated 29 September 2026 that amends Chapter XIV of the Sales Tax Rules. It applies the e-invoicing rules to federal excise duty and Islamabad services tax, adds excise fields, requires electronic notes and advance receipt invoices, and lets officers recover tax on FBR-numbered invoices missing from a return.
Do we need a second integration for federal excise? No. A person already integrated with FBR’s system for sales tax does not need a separate technical integration for excise or Islamabad services tax, and an integrator’s existing licence covers them.
Can one invoice show sales tax and excise together? Yes. Where sales tax, federal excise duty and Islamabad services tax are charged on the same transaction, one electronic invoice is enough if each tax is shown separately.
Do credit notes now have to be electronic? Yes. Under rule 150S of the Sales Tax Rules, as amended by SRO 1666, debit notes, credit notes and advance receipt invoices must be issued electronically and kept for six years.
Has FBR updated the API for the excise fields? Not as at 1 October 2026. FBR still links digital invoicing API version 1.12. Prepare your product data now and wait for the published specification before changing integrations.
Related reading: FBR deadlines and notifications, correcting an FBR invoice and the Finance Act 2026 penalties.
Ready to simplify your FBR digital invoicing?
Join 2000+ businesses that use eInvoicePro to make invoices and send them to FBR.