e-VHF integration — complete 2026 guide.
In AR since 2017, e-VHF (Electronic VAT Invoice) is mandatory for taxpayers with turnover above 200,000 AZN. This guide covers technical integration, common errors and best practices.
What is e-VHF and who needs it?
e-VHF is the AR State Tax Service's electronic invoice system. Mandatory for taxpayers with annual turnover over 200,000 AZN, voluntary for smaller. Instead of paper invoices, invoices are created electronically, signed with ASAN İmza and sent to the AR Tax Service server. Customer receives in their e-VHF inbox, must respond (accept or reject).
Technical requirements
1. e-VHF inbox — registration at online.taxes.gov.az 2. ASAN İmza — for company signing the director (or authorized) needs ASAN İmza certificate 3. API access — for direct e-VHF sending from software (provided by tax authority) 4. Software — COMPLEX.AZ, 1C or other integrated system
Integration in 4 phases
Phase 1: Preparation (1-2 days) — e-VHF inbox registration, ASAN İmza certificate, API access request Phase 2: Configuration (1-2 days) — enter tax inbox login + API key in software, link ASAN İmza certificate, test e-VHF (sandbox) Phase 3: Test process (1 week) — real invoices parallel: paper + e-VHF, fix errors, train accounting and sales staff Phase 4: Full migration — paper completely stopped, all invoices via e-VHF
Common errors and solutions
Error: "Signature does not match requirements" — ASAN İmza certificate person is not the director or no authorization. Solution: use director's ASAN or register authorization document at Tax Service. Error: "Buyer VÖEN not found" — invalid VÖEN. Solution: verify at online.taxes.gov.az. COMPLEX.AZ automatically validates VÖEN. Error: "Wrong VAT rate" — product category doesn't match VAT rate. Solution: verify NACE codes and VAT rate matching.
Best practices
- ✓Daily check e-VHF inbox — customers accepted or rejected?
- ✓Keep correction reports in separate folder
- ✓Monthly compare: cashier sales vs e-VHF sent
- ✓Backup — software database and e-VHF inbox monthly
- ✓Monitor ASAN İmza expiration — alert 30 days before expiry
How e-VHF works in COMPLEX.AZ
1. Order processed (POS, B2B portal, any channel) 2. Delivery confirmed 3. System auto-generates e-VHF (customer data from CRM, prices from order, VAT auto-calculated) 4. Signed with ASAN İmza (director gets push notification) 5. Sent to Tax Service, lands in customer inbox 6. When customer accepts, status changes to "Accepted" Full process: 30-60 seconds — 10× faster than paper invoice.
Free audit
To optimize your e-VHF process: [email protected] — free 30-min consultation, industry-specific advice.