Quick answer: CBMS (Central Billing Monitoring System) is the Inland Revenue Department’s central server that receives a copy of every invoice issued by approved billing software in Nepal, in real time. If your business uses electronic billing, each sales invoice you print is also reported to the IRD the moment it is created — that is what makes a bill “CBMS-connected”. The system exists so the IRD can match what businesses bill against what they later declare in VAT returns.
Where does CBMS come from?
CBMS is the enforcement arm of the Electronic Billing Procedure 2074 (2017), the IRD rule that governs how software-generated invoices must behave in Nepal. The procedure requires approved billing software to keep invoices tamper-proof, number them sequentially, and transmit invoice data to the IRD’s central system. When people ask whether a billing package is “IRD approved”, CBMS connectivity is a large part of what is actually being approved.
What data does CBMS receive?
For each bill, the reporting software sends the core invoice facts to the IRD’s API — broadly:
- Seller PAN and buyer PAN (where the buyer has one)
- Invoice number and the fiscal year it belongs to
- Invoice date — in both Bikram Sambat and the equivalent AD timestamp
- Taxable amount, VAT amount and total
- Whether the record is a sale or a credit-note reversal, and whether it was reported in real time or synced later
The IRD’s server acknowledges each submission. If your internet connection is down when the bill is issued, compliant software queues the invoice and reports it as a batch/sync record once the connection returns — flagged as such, so the IRD can tell live reporting from catch-up reporting.
Who must use CBMS-connected billing?
The IRD has phased electronic-billing obligations in by taxpayer size and sector rather than switching every business over at once. Large taxpayers and specific sectors were brought in first, and the net has widened over time. Two practical rules of thumb:
- If you are VAT-registered and issue invoices from software (rather than a manual bill book), that software is expected to comply with the Electronic Billing Procedure — using unlisted software is the compliance risk.
- If the IRD has notified your business or sector specifically, CBMS-connected billing is not optional.
When in doubt, ask your tax officer or CA whether your registration falls under a notification — and treat “the software prints a nice invoice” as a separate question from “the software reports to the IRD”.
What does CBMS change day to day?
| Before CBMS | With CBMS-connected billing |
|---|---|
| Invoices lived only in your system until you filed the VAT return | Every invoice reaches the IRD as it is issued |
| Editing or deleting a bill after the fact was technically possible in some software | Bills are immutable — corrections must go through credit notes, which are also reported |
| The VAT return was the first time the IRD saw your sales | Your return is cross-checked against bills the IRD already holds |
| Print format varied by vendor | Invoice content and numbering must follow the prescribed format |
Does CBMS mean the IRD sees my bills instantly?
For real-time-connected software, effectively yes — that is the design. What matters for you is the discipline it enforces: because a reported bill cannot be quietly altered, the correct way to fix a mistake is a credit note (for sales) or debit note (for purchases), which creates an auditable reversal instead of a silent edit. We cover this in detail in Can you edit or delete a tax invoice in Nepal?
Where Udyot ERP stands
Udyot ERP is IRD-verified with CBMS integration built in (approval no. 8301582, dated Ashad 32, 2083 BS): bills report to the IRD’s central system in real time when e-billing is enabled for your company, with offline queuing and flagged batch sync when the connection drops. Underneath sit the fundamentals the procedure demands — sequential fiscal-year invoice numbering, immutable tax invoices with credit-note corrections, VAT registers and annex exports in the IRD’s formats, and Bikram Sambat dating throughout. See how billing works in the invoice documentation and the VAT returns guide.
Common questions
Is CBMS the same as “IRD approved billing software”?
Related but not identical. Approval covers the whole Electronic Billing Procedure — invoice format, numbering, immutability, audit trail — of which CBMS reporting is the transmission piece. A vendor can claim “electronic billing” without being connected; listed, connected software is what the IRD recognises.
What happens if my internet goes down?
Compliant software keeps billing and queues the records, then syncs them flagged as batch submissions. You do not stop trading because the connection dropped.
Does CBMS apply to credit notes too?
Yes — reversals are reported like sales, which is exactly why untraceable deletions are impossible in a compliant system.
This article describes the system in general terms for business owners. Rules and notifications change — confirm your specific obligations with ird.gov.np or your CA.