Factur-X API for Digital Agencies and Integrators
Deliver Factur-X 2026 compliance to your SME clients in 2 days of Laravel dev. Create one sub-tenant per client, bill €5–10/month pass-through. Zero EN16931 liability for the agency.
$api = ScellApiClient::withApiKey('sk_live_...');
$invoice = $api->invoices()->builder()
->outgoing()
->facturX()
->issueDate('2026-05-16')
->dueDate('2026-06-15')
->buyer('98765432109876', 'Acme SARL',
new Address('2 av Client', '75002', 'Paris'))
->addLine('Consultation', 10, 150.00, 20.0)
->create();
echo $invoice->invoice_number; // FAC-202605-00123✓ FAC-202605-00123 — PDF/A-3b + XML CII EN16931
Typical client context
Julien Moreau
Gérant agence web Laravel
5–15 ETP · Laravel / Symfony
“Julien runs a 10-developer Laravel agency based in Lyon. Three SME clients contacted him urgently in January 2026 to add Factur-X invoicing to their custom ERPs. He is looking for a solution to integrate in 2 days and bill €5–10/month/client as pass-through.”
Common blockers
- 1SME clients have required Factur-X since the 2026 reform but the EN16931 standard is too complex to implement alone
- 2The risk of engaging agency liability in case of Factur-X non-compliance at a client is real
- 3Each SME client has a different Laravel or Symfony project — a fast and standardized integration is needed
- 4Training a junior developer on Factur-X standards (BT-84, BG-22, type 386/380) takes 2–3 weeks
- 5Without a solution, clients risk losing customers to competitors or losing B2B contracts
- 6Managing Factur-X standard updates for each client separately generates unmanageable technical debt
The Scell.io response
Day 1: `composer require scell/sdk`, `sk_test_*` key, first successful `$api->invoices()->builder()->create()` call. Day 2: integrate into the client's existing workflow (invoice form, status webhook, PDF export). One sub-tenant per SME client — the `app.scell.io` multi-tenant dashboard lets you supervise all client invoicing from a single login. Scell.io pricing: €0.04/invoice. An SME client issuing 50 invoices/month = €2 cost — rebilled at €5–10/month with comfortable margin. Factur-X updates (V2.2, FNFE schematron) are deployed by Scell.io with no API changes.
PHP SDK `scell/sdk`
`composer require scell/sdk`, no Laravel-specific dependency, Symfony 6.4+ compatible
Multi-tenant dashboard
supervise all SME clients from a single `app.scell.io` login, delegate read access
Standards maintained by Scell.io
EN16931, FNFE schematron, Factur-X V2.2: zero technical debt for the agency
Sub-tenant per client
ISCA ledger and invoicing for each SME strictly isolated under your master key
Free `sk_test_*` sandbox
test the integration without fiscal risk, validate on `validation.factur-x.eu`
Profitable pass-through
€0.04/invoice Scell.io cost, resold at €5–10/month/client, 250–500% margin on API cost
Context & stakes
Laravel agencies and Symfony integrators are on the front line of the 2026 e-invoicing reform. SME clients have been arriving urgently since early 2026 — and have no EN16931 specialist in-house. The agency must deliver quickly, without mistakes on compliance, and ideally turn the project into a monthly recurring service. Scell.io is designed for this model: `composer require scell/sdk`, one sub-tenant per SME client, and the builder pattern `$api->invoices()->builder()` integrates into any existing Laravel or Symfony project in under 2 days. Compliance responsibility (FNFE schematron, EN16931, LFR 2022 reform) rests with Scell.io server-side. The agency delivers a turnkey service and bills a monthly subscription without risking liability for each client's fiscal compliance.
Real-world use cases
- Laravel agency integrating Factur-X into a custom ERP for an industrial B2B SME client in 2 days
- Local IT company deploying Scell.io for 10 SME clients in a pooled service under one master key
- Symfony agency adding eIDAS SES signature to quotes for a service provider client
- Integrator creating a WooCommerce/WordPress module via Scell.io REST API for B2B e-commerce
- Agency billing 2-day integration project + monthly Scell.io subscription as pass-through
- Laravel freelancer offering Factur-X compliance as a recurring service to existing clients
Frequently asked questions
How long does it take to integrate Scell.io into an existing Laravel project?
Maximum 2 days for a senior Laravel developer: day 1 — `composer require scell/sdk`, configure `sk_test_*` key, first successful API call with the builder pattern; day 2 — integrate into existing workflow (invoice creation from SME form, status webhook, PDF export). The Swagger UI documentation lists 135 endpoints with ready-to-copy PHP and curl examples.
Is the agency liable for Factur-X non-compliance at their client?
Scell.io maintains Factur-X compliance (FNFE schematron, EN16931:2017+A1:2019, Factur-X V2.2) server-side. If the standard evolves, Scell.io deploys the update with no API changes. The agency's liability is limited to the correct technical integration of mandatory fields (SIRET, address, lines). Compliance of the generated Factur-X file is Scell.io's responsibility.
How do agencies bill Scell.io to their SME clients?
Pass-through model: subscribe to Scell.io under your name, create a sub-tenant per client, rebill with your margin. Scell.io usage-based pricing: €0.04/electronic invoice + €1.20/signer for eIDAS signature. An SME client issuing 50 invoices/month = €2 Scell.io cost. Rebilled at €5–10/month as SaaS, the margin is 250 to 500% on the API cost.
Does Scell.io work with Symfony?
Yes. The PHP SDK `scell/sdk` is a standard Composer package compatible with PHP 8.2+, Symfony 6.4+, Laravel 10+ and any PHP framework. It has no dependency on Laravel components. Standard Symfony dependency injection (`Scell\Sdk\ScellApiClient`) works via the service container.
How to test Factur-X integration at a client before going live?
The `sk_test_*` key points to an isolated sandbox database. Invoices issued in sandbox are not transmitted to the Peppol network. The generated Factur-X file can be validated at `validation.factur-x.eu` by downloading the PDF and verifying the embedded CII XML. Once compliance is validated, replace `sk_test_*` with `sk_live_*`.
Can a billing dashboard be created for SME clients without a dedicated UI?
The Scell.io dashboard (`app.scell.io`) offers a native multi-tenant view: single login, access to all your client sub-tenants, ISCA chains, daily closings and per-client billing KPIs. You can delegate read access to your SME client so they view their own invoices without touching the main dashboard.
Deliver Factur-X 2026 compliance to your next client in 2 days
`composer require scell/sdk`. One sub-tenant per SME client. EN16931 and Factur-X V2.2 standards maintained by Scell.io — zero technical debt for the agency.