REST API • ELECTRONIC INVOICING & FISCAL COMPLIANCE

Apex Balance

“The fiscal invoicing API developers actually enjoy integrating.”

Issue Invoices, Receipts, Credit Notes, and Dispatch Guides in milliseconds. Send a standard JSON payload and we handle digitally signed XML UBL 2.1, tax authority validation, status receipts (CDR), and automatic PDF generation.

REST API JSON Latency < 200ms UBL 2.1 + CDR Validation Free Sandbox
View Plans & Pricing ↓ Request API Key →
POST /api/v1/invoices
// Request: Issue in a single API call
curl -X POST https://api.apexcorpsac.com/v1/invoices \
  -H "Authorization: Bearer sk_live_apex_..." \
  -d '{
    "type": "01", // Electronic Invoice
    "series": "F001",
    "customer": { "tax_id": "20614557126", "legal_name": "ENTERPRISE CORP" },
    "items": [{ "description": "SaaS Subscription", "total": 118.00 }]
  }'

// Response (200 OK in 180ms)
{
  "status": "ACCEPTED",
  "invoice_number": "F001-00004521",
  "tax_authority_response": "The Invoice has been accepted.",
  "pdf_url": "https://cdn.apexcorpsac.com/F001-4521.pdf"
}
[ PERFORMANCE & FISCAL RELIABILITY ]

Infrastructure Engineered to Never Stop Your Checkout

< 200 ms
Average issuance latency including XML digital signature
99.95%
API availability with asynchronous retry queues during tax authority downtime
100%
Compliance with UBL 2.1, signed CDR, and official QR standards
[ DEVELOPER EXPERIENCE FIRST ]

Everything You Need for Frictionless Invoicing

Engineered to integrate electronic invoicing into your e-commerce, SaaS, ERP, or POS in a single afternoon.

JSON In • XML + CDR Out

Say goodbye to handling complicated XML tags or managing digital certificates on your servers. Send standard JSON and we handle the digital signature and tax authority validation.

Digital Signing Included Native UBL 2.1
Real-Time Webhooks

Receive automatic notifications on your backend whenever an invoice is accepted, rejected, or queued. Sync your databases instantly without resource-heavy polling.

HTTP POST Events Exponential Backoff
Free Sandbox & Test Tax IDs

Develop and test your entire checkout and sales flow with zero fees. 100% production-parity sandbox environment to simulate edge cases and credit notes.

Unlimited Testing Instant Provisioning
Automated PDF in 3 Formats

Automatic printed representation rendering in A4, 80mm Receipt, and 58mm POS with corporate logo, QR codes, and barcodes.

Multi-Tenant & Multi-Company

Building a SaaS or app for multiple businesses? Manage dozens of tax entities with segregated API keys and monitor consumption per client in one unified console.

Tax Authority Downtime Resilience

If the tax authority server experiences intermittent outages, Balance safely queues signed documents and retries automatically without blocking checkout flow.

[ TRANSPARENT PRICING ]

Flexible Pricing for Every Stage of Your Business

Choose between Prepaid Credit Packs (pay-as-you-go without rapid expiration), Monthly Subscriptions with included documents, or the Corporate On-Demand Model.

OPTION 1

Prepaid Credit Packs (Pay-as-you-go for Devs & Side Projects)

Ideal for building MVPs, freelance client projects, or variable-volume business models. Buy a document pack and consume it at your own speed.

Testing
Sandbox / Free
$0 / forever
  • • 20 test documents included
  • • Sandbox environment access
  • • UBL 2.1 & XML validation
  • • Community technical support
Start Free
Kickstart
Side Project
$4.50 one-time (~S/ 15)
  • • 100 documents included
  • • Invoices, Receipts & Credit Notes
  • • PDF A4 & POS Ticket generation
  • • Live Webhook dispatch
Get Pack
Popular Devs
Freelance
$11.50 one-time (~S/ 39)
  • • 300 documents included
  • • Production fiscal issuance
  • • Batch XML & CDR download
  • • Direct technical support
Get Pack
Agencies
Agency
$18.00 one-time (~S/ 61)
  • • 600 documents included
  • • Multi-client support
  • • Real-time status console
  • • Priority support
Get Pack
OPTION 2

Monthly Subscription Model (Enterprises & SaaS)

Engineered for companies and platforms with recurring monthly invoice volume. Includes recurring allowances and discounted document rates.

Starter
$8.50 / mo (~S/ 28)

200 documents included / month

For small stores and emerging businesses.

Subscribe Starter
Growth
$18.00 / mo (~S/ 61)

600 documents included / month

For growing retail, active e-commerce and restaurants.

Subscribe Growth
Recommended
Scale
$52.00 / mo (~S/ 178)

3,000 documents included / month

For high-traffic operations, chains and multi-POS setups.

Subscribe Scale
APEX
$220.00 / mo (~S/ 740)

20,000 documents included / month

For enterprise retail chains, marketplaces, and wholesalers.

Subscribe APEX
OPTION 3

Corporate On-Demand Model (ERP / Mass Invoicing)

1. Base Platform Fee
$29.00 / mo (~S/ 99)

Full platform access, multi-company dashboard, segregated API Keys with customized rate limiting, real-time telemetry, and 24/7 priority SLA support.

2. Variable Usage Per Document
$0.024 / successful document (~S/ 0.08)

Transparent billing solely for successfully accepted documents. Zero charges for rejected submissions or sandbox tests. Invoiced monthly in arrears.

[ DIRECT CONTACT ]

Request Your Sandbox API Key or Technical Consultation

Leave your contact details and our integration team will provide sandbox credentials and complete API documentation.

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