This guide is for business owners, finance managers and operations leads in Nepal who issue tax invoices or sales bills from software — or who are preparing to move from handwritten invoice pads and spreadsheets to a digital billing system. It explains how the Inland Revenue Department (IRD) regulates electronic invoicing and the Central Billing Monitoring System (CBMS), what your software must never allow, and what to check before you buy or commission a billing system.
Nepali edition: नेपालमा IRD विद्युतीय बीजक र CBMS सफ्टवेयर गाइड
Electronic billing vs CBMS: two related requirements
In everyday conversation in Nepal, people call every tax-compliant billing program “IRD software”. Technically, the IRD rules cover two layers:
- Electronic Billing (विद्युतीय बीजक): issuing invoices from IRD-enlisted computer software instead of pre-printed paper pads, following the IRD’s Procedures Relating to Electronic Invoicing (विद्युतीय बीजक सम्बन्धी कार्यविधि).
- Central Billing Monitoring System (CBMS): real-time or near-real-time transmission of invoice and credit-note metadata from your billing software to the IRD’s central server through the CBMS API.
Whether your business must use electronic billing — and whether it must also sync with CBMS — depends on your VAT registration status, annual turnover threshold and business sector (such as hotels, restaurants, hospitals, wholesalers or manufacturers) as notified by the IRD under the Value Added Tax Act, 2052 (1996) and Income Tax Act, 2058 (2002). Always check the current IRD notices with your auditor or tax officer for your exact turnover bracket.
The core engineering rules of IRD-compliant billing software
An ordinary open-source invoicing tool or generic international ERP often fails IRD compliance out of the box because international tools allow users to edit or delete finalized invoices. Under IRD electronic billing standards, once an invoice is issued, it becomes a permanent tax record.
| Requirement | Non-compliant software | IRD-compliant software |
|---|---|---|
| Editing or deleting an issued invoice | Allows an admin to edit line items or delete a bill | Strictly blocked; no edit or delete button exists for issued invoices |
| Correcting a mistake or return | Overwrites the original invoice | Issues a linked Credit Note (क्रेडिट नोट) or cancellation entry with a recorded reason |
| Invoice numbering | Manual or resettable at any time | Strictly sequential per fiscal year (आर्थिक वर्ष, Shrawan to Ashadh), gap-free |
| Reprinting an invoice | Prints an identical “Tax Invoice” every time | Marks the first print as Tax Invoice (or Invoice) and every subsequent print as Copy of Original (प्रतिको प्रतिलिपि) with a reprint counter |
| Audit log (प्रयोगकर्ता लग) | Minimal or editable | Immutable activity log tracking who created, printed or cancelled an entry and when |
| Calendar support | Gregorian (AD) only | Supports Bikram Sambat (BS) fiscal year dates alongside AD |
How CBMS real-time synchronization works
When a business is connected to the IRD’s Central Billing Monitoring System, each finalized sales invoice or sales return is pushed to the IRD’s API endpoint using credentials issued specifically for that taxpayer’s PAN/VAT number.
A well-engineered CBMS integration handles three practical realities of running a business in Nepal:
1. Internet outages at the billing counter
Internet connections drop, and the IRD server occasionally undergoes maintenance. Your counter cannot stop billing customers while the line is down. Good software records the invoice locally (or on your primary server) with a cbms_sync_pending flag, prints the customer’s bill immediately, and runs a background queue that transmits pending invoices to CBMS in exact sequence as soon as connectivity returns.
2. Testing before going live
The IRD provides a CBMS test environment so developers can verify payload fields — seller PAN, buyer PAN, fiscal year (2082/83, etc.), invoice number, invoice date in BS, taxable amount, VAT amount and sync flags (isrealtime: true or false when synced after an offline period) — before any live tax data is sent.
3. Reconciling CBMS totals with your monthly VAT return
Before filing your monthly VAT return on the 25th of the following BS month, your accountant should compare three figures:
- Your billing software’s Sales Register (बिक्री खाता)
- Your Credit Note / Sales Return Register
- The CBMS portal summary under your taxpayer login at
ird.gov.np
If five invoices sat in an failed sync queue because of a network timeout or a malformed buyer PAN, catching them before the 25th takes two minutes; catching them during a tax audit is painful.
Buying off-the-shelf vs building custom billing software
Not every business should build its own billing software from scratch.
- When an off-the-shelf IRD-enlisted package is best: if your business is a standard retail shop, pharmacy, hardware store or standalone restaurant, an existing IRD-listed accounting or POS system is faster and more economical.
- When custom software or integration makes sense: if your revenue comes from specialized operations — such as a multi-branch service business, a logistics network, a booking platform or an industry workflow like laundry, manufacturing or field distribution — typing every order twice (once in your operational system and once in a separate billing program) creates daily human error.
In those cases, you have two clean architectural options:
- Integrate your custom system with an IRD-listed accounting engine so operational orders generate compliant invoices without double entry.
- Enlist your own software with the IRD by following the IRD software specification, audit checklist and application process for your company.
Checklist before you choose or sign off on billing software
- Ask for the software’s IRD enlistment letter / specification compliance details, and confirm whether your business falls under the CBMS threshold.
- Verify that issued invoices cannot be edited or deleted, even by the highest administrator account.
- Test reprinting an invoice: confirm the second print clearly shows Copy of Original and increments the print count.
- Test issuing a Credit Note: confirm it links to the original invoice number, requires a reason, and updates the Sales Return register.
- Test offline mode: disconnect the internet, issue two bills, reconnect, and verify that both bills sync with
isrealtime = falsewithout duplicating invoice numbers. - Check data export and backups: ensure you can export the IRD-format Sales Register (बिक्री खाता) and Purchase Register (खरिद खाता) and that encrypted off-site backups run automatically every day.
Need your operational software and billing to work together?
We build web applications, desktop software and systems integrations for businesses in Nepal that want their day-to-day operations, payments and accounting records to match without double entry. If you’re planning a system, talk to us.
Sources
- Inland Revenue Department (IRD), Government of Nepal: Official portal and taxpayer services, https://ird.gov.np/
- Law Commission of Nepal: Value Added Tax Act, 2052 (1996), https://lawcommission.gov.np/
- Law Commission of Nepal: Income Tax Act, 2058 (2002), https://lawcommission.gov.np/
- Inland Revenue Department (IRD): Procedures Relating to Electronic Invoicing (विद्युतीय बीजक सम्बन्धी कार्यविधि) and CBMS technical specifications published on https://ird.gov.np/