Application Programming Interface

InvoiceXpress Documentation


POST /:document-type.json

Creates a new invoice, simplified_invoice, invoice_receipt, credit_note or debit_note.

Creating new clients or items along with the invoice

This method also allows to create a new client and/or new items in the same request with the following behavior:

  • If the client name does not exist a new one is created.
  • If items do not exist with the given names, new ones will be created.
  • If item name already exists, the item is updated with the new values.


Regarding item taxes, if the tax name is not found, the default tax is applyed to that item. Portuguese accounts should also send the IVA exemption reason if the invoice contains exempt items (IVA 0%).

Note: Simplified Invoices are only available in Portugal.

Example URL


You can find your ACCOUNT_NAME and API_KEY here: https://www.app.invoicexpress.com/users/api

Example Request


curl --request POST \
  --url 'https://account_name.app.invoicexpress.com/:document-type.json?api_key=YOUR%20API%20KEY%20HERE' \
  --header 'accept: application/json' \
  --header 'content-type: application/json' \
  --data '{"invoice":{"date":"03/12/2017","due_date":"03/12/2017","client":{"name":"Client Name","code":"A1"},"items":[{"name":"Item Name","description":"Item Description","unit_price":"100","quantity":"5"}]}}'


require 'uri'
require 'net/http'

url = URI("https://account_name.app.invoicexpress.com/:document-type.json?api_key=YOUR%20API%20KEY%20HERE")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true
http.verify_mode = OpenSSL::SSL::VERIFY_NONE

request = Net::HTTP::Post.new(url)
request["accept"] = 'application/json'
request["content-type"] = 'application/json'
request.body = "{\"invoice\":{\"date\":\"03/12/2017\",\"due_date\":\"03/12/2017\",\"client\":{\"name\":\"Client Name\",\"code\":\"A1\"},\"items\":[{\"name\":\"Item Name\",\"description\":\"Item Description\",\"unit_price\":\"100\",\"quantity\":\"5\"}]}}"

response = http.request(request)
puts response.read_body


var http = require("https");

var options = {
  "method": "POST",
  "hostname": "account_name.app.invoicexpress.com",
  "port": null,
  "path": "/:document-type.json?api_key=YOUR%20API%20KEY%20HERE",
  "headers": {
    "accept": "application/json",
    "content-type": "application/json"

var req = http.request(options, function (res) {
  var chunks = [];

  res.on("data", function (chunk) {

  res.on("end", function () {
    var body = Buffer.concat(chunks);

req.write(JSON.stringify({ invoice:
   { date: '03/12/2017',
     due_date: '03/12/2017',
      { name: 'Client Name',
        code: 'A1'},
      [ { name: 'Item Name',
          description: 'Item Description',
          unit_price: '100',
          quantity: '5' } ],


import http.client

conn = http.client.HTTPSConnection("account_name.app.invoicexpress.com")

payload = "{\"invoice\":{\"date\":\"03/12/2017\",\"due_date\":\"03/12/2017\",\"client\":{\"name\":\"Client Name\",\"code\":\"A1\"},\"items\":[{\"name\":\"Item Name\",\"description\":\"Item Description\",\"unit_price\":\"100\",\"quantity\":\"5\"}]}}"

headers = {
    'accept': "application/json",
    'content-type': "application/json"

conn.request("POST", "/:document-type.json?api_key=YOUR%20API%20KEY%20HERE", payload, headers)

res = conn.getresponse()
data = res.read()




curl_setopt_array($curl, array(
  CURLOPT_URL => "https://account_name.app.invoicexpress.com/:document-type.json?api_key=YOUR%20API%20KEY%20HERE",
  CURLOPT_POSTFIELDS => "{\"invoice\":{\"date\":\"03/12/2017\",\"due_date\":\"03/12/2017\",\"client\":{\"name\":\"Client Name\",\"code\":\"A1\"},\"items\":[{\"name\":\"Item Name\",\"description\":\"Item Description\",\"unit_price\":\"100\",\"quantity\":\"5\"}]}}",
    "accept: application/json",
    "content-type: application/json"

$response = curl_exec($curl);
$err = curl_error($curl);


if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;


package main

import (

func main() {

  url := "https://account_name.app.invoicexpress.com/:document-type.json?api_key=YOUR%20API%20KEY%20HERE"

  payload := strings.NewReader("{\"invoice\":{\"date\":\"03/12/2017\",\"due_date\":\"03/12/2017\",\"client\":{\"name\":\"Client Name\",\"code\":\"A1\"},\"items\":[{\"name\":\"Item Name\",\"description\":\"Item Description\",\"unit_price\":\"100\",\"quantity\":\"5\"}]}}")

  req, _ := http.NewRequest("POST", url, payload)

  req.Header.Add("accept", "application/json")
  req.Header.Add("content-type", "application/json")

  res, _ := http.DefaultClient.Do(req)

  defer res.Body.Close()
  body, _ := ioutil.ReadAll(res.Body)


Path Parameters

document-typeStringRequiredThe type of document you want to create. For example: invoicessimplified_invoicesinvoice_receiptscredit_notes or debit_notes.invoices

Request Body

invoiceObjectRequiredInvoice data to be created
dateStringRequiredThe invoice date. Must be in format dd/mm/yyyy ex.: 03/12/2015. If format is invalid, date will be set to current date.
due_dateStringRequiredThe invoice due date. Must be in format dd/mm/yyyy ex.: 03/12/2015. If format is invalid, date will be set to current date.
referenceStringThe invoice purchase order reference field.
observationsStringInvoice observations, these will be printed with the invoice.
retentionStringWithholding tax percentage (%). Must be a number between 0 and 99.99.
tax_exemptionStringDependsPortuguese IVA exemption code. Required for portuguese accounts on invoices with IVA exempt items (0%). Refer to the Appendix for the complete list of “IVA Exemption Codes”.
sequence_idStringId of the sequence you want to use with this invoice. If missing, the default sequence will be used.
manual_sequence_numberStringDependsRequired for non portuguese accounts with manual sequence numbering.
nameStringRequiredThe invoice’s client. If the client doesn’t exist, a new one is created. If it exists, the remaining client fields will be ignored.
codeStringRequiredThe client’s unique code. If the client doesn’t exist, a new one is created. If it exists, the remaining client fields will be ignored.
emailStringClient email address. Must be a valid email address ex: foo@bar.com
addressStringClient company address.
cityStringClient’s city.
postal_codeStringClient’s postal code for it’s company address.
countryStringCountry, normally used for a company country. Although country is optional, when supplied, it should match one of the country list on the Appendix of this Documentation.
fiscal_idStringThe client fiscal ID (Número de Contribuinte)
websiteStringThe client web address
phoneStringThe client phone number
faxStringThe client fax number
observationsStringThe client default observations. This is added to the observations field of all the invoices sent to this client.
itemsArrayRequiredAn array of invoice items. If items with the given names do not exist, they are created. If an item already exists, it is updated with the new values. At least one is required.
nameStringRequiredName of the item. Must be unique.
descriptionStringRequiredItem’s description
unit_priceNumberRequiredItem’s unit price. Must be a number equal or greater than 0.0.
quantityNumberRequiredQuantity. Must be a number equal or greater than 0.
unitStringThe item unit of measure
discountNumberThe item discount percentage(%). Defaults to 0.0. Must be a value between 0.0 and 100.0 inclusive.
taxObjectThe tax applied to the item line. If not present the default tax is applied to the item
nameStringThe tax name to be used on this item line. If not found the default tax is applied to the line item
mb_referenceStringGenerates a Multibanco Reference after you finalize your invoice. This option is only available for Portuguese Accounts. You must have the feature enabled on your account first.
owner_invoice_idIntegerThe (owner) invoice associated to this document. This option is only available for credit_notes or debit_notes. You can also send the (owner) guide id when creating an invoice to associate an invoice to a guide.
tax_exemption_reasonStringUsed when updating a document and removing all tax exempt items. The code M00 means ‘Without tax exemption’.
currency_codeStringIf your plan as multicurrency, you can issue invoices in another currency than your account’s default currency. The currency_code should be one of the following ISO 3166 alpha-2 currency codes.
rateStringWhen sending a currency_code you can specify its’ rate.
proprietary_uidStringWhen sending your process’ UUID you will prevent the creation of duplicate requests.
global_discountObjectThe discount applied to the document
value_typeStringValue type can be percentage or absolute
valueNumberDocument’s global discount value. Must be a number greater than 0.0
plugin_idStringThis is used by plugin owners to include in the creation of their user’s invoices. Please reach out for our support team at plugins@rupeal.com if you are interested in developing a new plugin.

Example Request Body

  "invoice": {
    "date": "03/12/2017",
    "due_date": "03/12/2017",
    "reference": "999",
    "observations": "Observations",
    "retention": "0",
    "tax_exemption": "M01",
    "sequence_id": "12345",
    "manual_sequence_number": "1",
    "client": {
      "name": "Client Name",
      "code": "A1",
      "email": "foo@bar.com",
      "address": "Saldanha",
      "city": "Lisbon",
      "postal_code": "1050-555",
      "country": "Portugal",
      "fiscal_id": "508000000",
      "website": "www.website.com",
      "phone": "910000000",
      "fax": "210000000",
      "observations": "Observations"
    "items": [
        "name": "Item Name",
        "description": "Item Description",
        "unit_price": "100",
        "quantity": "5",
        "unit": "service",
        "discount": "50",
        "tax": {
          "name": "IVA23"
    "mb_reference": "0",
    "owner_invoice_id": "12345",
    "tax_exemption_reason": "M00",
    "currency_code": "USD",
    "rate": "1.23565",
    "global_discount": {
      "value_type": "percentage",
      "value": 50.0
  "proprietary_uid": "UUID41237123189981ddajkls23478y"


Invoice was created successfully.
Invoices Get
The API Key parameter is missing or is incorrectly entered.
(Empty Response)
There’s an ongoing document creation with the provided UID.
(Empty Response)
Some parameters were incorrect.
(Empty Response)

Example Success Body Response

  "invoice": {
    "id": 2137287,
    "status": "draft",
    "archived": false,
    "type": "Invoice",
    "sequence_number": "6/G",
    "inverted_sequence_number": "G/6",
    "atcud": "ABCD1234-28",
    "sequence_id": "12345",
    "tax_exemption": "M01",
    "date": "04/08/2016",
    "due_date": "19/08/2016",
    "reference": "foo",
    "observations": "foo",
    "retention": "foo",
    "permalink": "https://www.app.invoicexpress.com/documents/213728738ca780a8de4330cad4a5a556360304bd9c57011",
    "saft_hash": "J4ay",
    "sum": 24.39,
    "discount": 0,
    "before_taxes": 24.39,
    "taxes": 5.61,
    "total": 30,
    "currency": "Euro",
    "client": {
      "id": 628535,
      "name": "John",
      "country": "Portugal"
    "items": [
        "name": "Large",
        "description": "foo",
        "unit_price": "24.3902",
        "unit": "foo",
        "quantity": "1.0",
        "tax": {
          "id": 69166,
          "name": "IVA23",
          "value": 23
        "discount": 0,
        "subtotal": 24.39,
        "tax_amount": 5.61,
        "discount_amount": 0,
        "total": 30
    "mb_reference": {
      "entity": "10611",
      "value": 30,
      "reference": "952000823"
    "global_discount": {
      "value_type": "percentage",
      "value": 50.0