Application Programming Interface

InvoiceXpress Documentation

Error codes responses

Code Text Description
200 OK Success!
201 Created Resource created successfully.
401 Access denied The API Key parameter is missing or is incorrectly entered.
404 Not Found The requested resource does not exist.
406 Not Acceptable The :document-id provided is in an invalid state.
422 Unprocessable Entity Some parameters were incorrect.

Possible errors for HTTP Status Code 422:

Invoices, Estimates and Guides

Send by Email

  • No content type or wrongly specified
  • Email: is an invalid email
  • Cc: is an invalid email
  • Bcc: is an invalid email

Create or Update

  • Items element should be of type array
  • Country Germani was not found
  • Retention must be a number between 0 and 99.99
  • Invoice items is invalid
  • Client is invalid
  • Due date must be later than date
  • Email must be an email address
  • Discount is not a number
  • Quantity must be a number greater than 0
  • Unit price must be a number
  • Unit kg is not included in the list of accepted units
  • Option to generate MB reference is set but no payment provider is configurated
  • Invoice has been settled so can't be changed anymore

Change State

  • Invalid state
  • Cancel message can't be blank


  • Name has already been taken
  • Client contact is invalid
  • Send options is not a number
  • Send options must be within 1 and 3
  • Preferred contact: email must be an email
  • Country Germani was not found


  • Postal Code must have the following format DDDD-DDD
  • Email is invalid
  • Vat Number can't be changed
  • Vat Number is already used in another account
  • Terms and Conditions must be accepted


  • Name has already been taken
  • Unit price can't be blank
  • Unit price is not a number
  • Unit kg is not included in the list of accepted units


  • Name has already been taken
  • Value can't be blank
  • Value must be a number between 0 and 99.99
  • Tax region is empty
  • Tax region is not valid


  • Serie has already been taken
  • The sequence name is invalid


  • That option is not available during the trial period, it becomes so only after the first payment.
  • There aren't any documents to export on the selected period.
  • Warning! There is required information missing from Company information. Before you export the SAF-T PT, please go to Company information and fill out the missing fields.
  • You need to send the month in the request body.