Which permissions do I need to ask for?

The catalogue is closed and uses permissions such as invoices:write or series:read. You choose them when creating the key. The quickstart only requests what it needs. Ask for one your plan does not include and the error fires at key creation, not halfway through the integration.

Does the API cover the same ground as the app?

The 50 resources run from quotes to the monthly time-tracking close and on to projects and tasks, by way of VeriFactu, e-invoicing for public bodies and tax reports. The rule is simple: if it is not in the public OpenAPI, it is not in the API.

Can I integrate without writing code?

Yes, through the MCP server: 581 tools an agent can use directly, or 468 when the connection comes from a third-party app over OAuth. Same API, same permissions, called from somewhere else.

What does the API cost?

API and MCP are included. Trial allows 10 requests a minute and 100 a month; Esencial, 30 and 5,000; Profesional and Avanzado, 300 and 50,000. Enterprise per contract. Throughput follows your plan; webhooks depend on the plan and permissions.

Developers · Invoicing API

Invoicing API.Built into your software.

Integrate invoices, customers, PDFs and Verifactu into your ERP, SaaS or online store. Use REST, official SDKs or MCP and validate the workflow in a test environment.

Create my test account Follow the Quickstart

API and MCP are included in paid plans. Limits depend on your plan.

Compatible integrations and formats

Factuarea APIv1

GET/v1/invoices invoices:read

1curl --fail-with-body --silent --show-error \2  "https://api.factuarea.com/v1/invoices" \3  --header "Authorization: Bearer $FACTUAREA_API_KEY"

1import { Factuarea } from "@factuarea/sdk";23const factuarea = new Factuarea({4  apiKey: process.env.FACTUAREA_API_KEY!,5});67const invoices = await factuarea.invoices.list();89for await (const item of invoices) {10  const invoice = item as { id: string };11  console.log(invoice.id);12}

1use Factuarea\Sdk\Custom\FactuareaClient;2use Factuarea\Sdk\Custom\Pagination\PageIterator;3use Factuarea\Sdk\Models\Operations\PublicApiV1InvoicesListRequest;45$factuarea = FactuareaClient::create(getenv('FACTUAREA_API_KEY'));6$pages = new PageIterator(7  fn (?string $cursor) => $factuarea->invoices->publicApiV1InvoicesList(8    new PublicApiV1InvoicesListRequest(startingAfter: $cursor),9  )->rawResponse,10);11foreach ($pages->items() as $invoice) {12  echo $invoice['id'], PHP_EOL;13}

Response excerpt 200 OK

FAC-2026-00042Acme Soluciones SL

1.210,00 €status: paid

Your applicationFactuarea APIJSON response

Use a key with invoices:read permission on your server. This code reads your invoices; it does not create documents.

Choose your integration

One account. Your way to build.

Connect your software, receive events or give an assistant access. Each path has its own guide, permissions and examples.

REST API

Your business documents, from your code.

Create customers and drafts, issue invoices and retrieve their PDF. The OpenAPI contract documents fields, permissions and errors for each operation.

1GET    /v1/contacts2POST   /v1/invoices3POST   /v1/invoices/{id}/send4GET    /v1/invoices/{id}/pdf

Customers, catalog, sales, expenses and reports in one API.

Explore the REST API

480 published routes50 resources

Read the full reference

Test before issuing

The same contract. Two separate environments.

Test your integration with a fact_test_ key. When it is ready, configure your company, review permissions and use a production key.

1Create a key with the permissions you need.
2Prepare the customer, series and taxes.
3Follow draft creation, issuance and PDF download.

Explore the sandbox Build my first invoice

api.factuarea.com/v1

Testing

fact_test_•••• •••• ••••

Test documents, with no real tax submission. Payments and WhatsApp are restricted.

Production

fact_live_•••• •••• ••••

Real documents and operations, subject to your company settings and plan.

Control over every request

Built for retries, too.

An integration needs to know what happened, what can be repeated and when to wait. These signals are documented and can be verified.

One operation, even when you retry

Original requestPOST /invoices

Same key and same bodyIdempotency-Key

Same result · no duplicate document

Prevent duplicates: Use Idempotency-Key on supported operations. A different body with the same key returns a 409.
Limited access: Assign scopes to each key. Your integration gets the permissions it needs for its work.
Visible quotas: Check X-RateLimit-Remaining. If you receive a 429, respect Retry-After before trying again.
Verifiable events: Check Factuarea-Signature against the original webhook body before processing it.

Review authentication and guarantees Check plans and limits

Choose your connection

An integration that fits your stack

Work with an SDK, explore the API contract or connect your assistant. Choose your tool to find the right starting point and documentation.

Compatible technologies and clients

Your tool → Factuarea

Official SDK

Your integration, in TypeScript

Install the official SDK to work with the API from Node.js. Includes retries, pagination and webhook signature verification.

npm install @factuarea/sdkConnect TypeScript

API operations: 595
resources: 50
MCP tools: 581
documentation pages: 1306

Questions

What gets asked before the first line of code

Create your account and a test key in developer settings. The Quickstart explains permissions, required data and the requests needed to take an invoice through to its PDF.

A more connected business

Your next integration starts with a key.

Create your account, choose permissions and follow the Quickstart to your first invoice in the test environment.

Start free Go to the quickstart