Beglaubigt.de API

GbR / eGbR

Create a tax registration for a GbR or eGbR (Personengesellschaft). Generates the ELSTER FsE_PersG form.

POST https://api.beglaubigt.de/v1/tax-registration

The request for a GbR or eGbR (Personengesellschaft). legal_form is gbr or egbr, which maps to the ELSTER FsE_PersG form. An eGbR is a GbR entered in the company register (Gesellschaftsregister); express it via the register fields below.

Authorization

Include an Authorization header with a Bearer token:

Authorization: Bearer <token>

Example: Bearer sk-123e4567-e89b-12d3-a456-426614174000

Environment

The environment comes from the company your API key belongs to, not from the request. A sandbox company's key creates sandbox registrations, filed against the ELSTER test environment; a production company's key creates live ones. To test, use the API key of your sandbox company.

The example tax ID 09481663279 is ELSTER's test IdNr: the sandbox accepts it, and production rejects it with 400 VALIDATION_ERROR. A production registration needs each person's real tax ID.

Idempotency

To retry a request safely after a timeout or a 5xx, send an Idempotency-Key header and reuse the same key on every retry. A retry then gets the first response back instead of creating a second case. See Idempotency.

Idempotency-Key: 5b0c8e8a-7d2f-4d0e-9a51-1f0b6a4c2e11

Request

Core

company_idstring

The UUID of the client company the tax registration belongs to. A company holds at most one tax registration and one trade registration, so use the same company_id on both endpoints to keep a client's registrations together, in parallel or in any order.

  • A UUID that does not exist yet: the company is created under that id. You can choose the id yourself.
  • An existing company of yours: the registration is added to it. If it already has a tax registration, the request returns 409 COMPANY_ALREADY_REGISTERED. If it is in another environment than your API key's company (see Environment), it returns 409 ENVIRONMENT_MISMATCH.
  • A company created by another account: 404 COMPANY_NOT_FOUND.
  • Omitted: a new company is created and its id returned as company_id.

Example: 9b2e4c7a-1d3f-4a8b-9c6e-2f5a7b8c1d0e

business_addressobject

Billing address of the client company created for you. Only applies when company_id is omitted; it is rejected if sent together with company_id.

legal_formstringrequired

The legal form of the company.
Possible values: gbr or egbr

packagestringrequired

The service package the client selected.
Possible values: self or assisted (guided is still accepted as a deprecated alias of assisted)

signature_pathstringrequired

The client's signature as an SVG path string (the drawn signature).
Example: M 10 10 L 90 90 M 90 10 L 10 90

client_referencestring

A custom reference string for your own tracking.
Example: REF-2025-001

Company & Founding

namestringrequired

Partnership name (Firmenname). Max 120 characters.
Example: Muster & Partner GbR

purposestringrequired

Description of the business activity. Max 200 characters.
Example: Grafikdesign und Beratung

operational_activity_start_datestringrequired

The date the business begins operating. Must not be before founding_date. Format: YYYY-MM-DD.
Example: 2025-03-01

founding_datestringrequired

Date the partnership was formed. Format: YYYY-MM-DD.
Example: 2025-03-01

founding_kindstringrequired

How the partnership came about: 1 new formation (Neugründung), 2 relocation (Verlegung), 3 takeover (Übernahme), 4 conversion (Umwandlung).
Possible values: 1, 2, 3 or 4

accounting_profit_methodstringrequired

Method used to determine taxable profit: 01 cash accounting (EÜR), 02 double-entry (Bilanz), 03 standard rates (Durchschnittssätze), 04 other (Sonstige).
Possible values: 01, 02, 03 or 04

addressobjectrequired

Registered business address (see the Address object).

Partners

directorsarrayrequired

Representatives (Vertreter). 1–99 entries.

shareholdersobjectrequired

Partners (Beteiligte), split into two arrays: individuals (natural persons) and entities (legal entities). At least 2 and at most 99 across both, and the share_percentage values must sum to 100.

individualsarray

Natural-person partners.

entitiesarray

Legal-entity partners.

Company Register

For an eGbR that is entered, intends to register, or has applied, supply the register state.

register_intendedboolean

Whether entry in the company register is intended (this is what turns a GbR into an eGbR).
Possible values: true or false

registration_numberstring

The register number, present once the eGbR has been entered.
Example: 12345

registration_datestring

Date of entry in the register. Format: YYYY-MM-DD.
Example: 2025-03-20

registration_application_filedboolean

Whether the registration application has been filed while the entry is still pending.
Possible values: true or false

registration_application_datestring

Date the registration application was filed. ELSTER needs it when registration_application_filed is true: without it ELSTER refuses the registration, and the request fails with 422 ELSTER_PLAUSIBILITY_ERROR. Format: YYYY-MM-DD.
Example: 2025-03-10

courtstring

Registering court. Required with a registration_number. ELSTER also needs it when registration_application_filed is true: without it ELSTER refuses the registration, and the request fails with 422 ELSTER_PLAUSIBILITY_ERROR.
Example: Frankfurt am Main

Bank Account

ibanstring

The company's bank account IBAN. For a non-German IBAN you must also supply bic.
Example: DE89370400440532013000

bicstring

The bank identifier (BIC/SWIFT) for the account, 8 to 11 characters. Required for non-German IBANs.
Example: COBADEFFXXX

Revenue & Profit Estimates

financial_estimatesobjectrequired

Estimated revenue and taxable profit for the formation year and the following year. All amounts are whole euros.

formation_yearobjectrequired

Estimates for the formation year (the year the business starts operating).

following_yearobjectrequired

Estimates for the year after the formation year.

VAT

vatobjectrequired

The company's VAT setup.

Employees & Payroll

has_employeesboolean

Whether there are employees. Enables the payroll block. When true, the fields below are all required.
Possible values: true or false

employee_countnumber

Number of employees. Required when has_employees = true.
Example: 4

shareholder_employee_countnumber

Number of employees who are also partners. Required when has_employees = true.
Example: 1

payroll_start_datestring

Start of wage payments. Must not be before operational_activity_start_date. Required when has_employees = true. Format: YYYY-MM-DD.
Example: 2025-05-01

estimated_annual_wage_taxnumber

Estimated annual wage tax (Lohnsteuer). Required when has_employees = true.
Example: 20000

Shared Objects

Addressobject

Response

A self registration is filed with ELSTER within the request. A request that fails validation, or that ELSTER refuses, is an error and creates nothing. An assisted one is reviewed by a lawyer before it is filed.

resultstring

Outcome of the request.
Possible values: success or error

messagestring

Human-readable outcome message.
Example: Tax registration filed with ELSTER.

company_idstring

UUID of the client company the case belongs to: the company_id you sent, or the one created for you when you omitted it. Pass it as company_id to the trade registration endpoint to register the same company there.
Example: 9b2e4c7a-1d3f-4a8b-9c6e-2f5a7b8c1d0e

tax_registration_idstring

UUID of the tax registration case. Use it with the GET endpoint.
Example: 450506c1-d1a7-46e2-aca6-41a816805595

statusstring

How far the registration got.
Possible values:

  • submitted: filed with ELSTER. transfer_ticket and documents are set.
  • validated: an assisted registration, waiting for the lawyer's review before it is filed.
  • blocked: rare. The filing failed in a way that may have reached ELSTER, so the case is kept and our team checks it with ELSTER and finishes it; the tax-registration.completed webhook and the GET endpoint report the result. Nothing to resend.
tax_officeobject

The tax office (Finanzamt) the registration is filed with, resolved from the address.

transfer_ticketstring

ELSTER's receipt for the filing, present when status is submitted.
Example: et1a2b3c4d5e6f7a8b9c0d1e2f3a4b5c6d

documentsobject

Download links for the filing's PDFs, present when status is submitted. Each link is valid for 24 hours; the GET endpoint returns fresh ones.

timestampstring

ISO 8601 timestamp of the response.
Example: 2025-02-01T07:19:30.443Z

Errors

Statuserror_codeWhenCreated
400VALIDATION_ERRORA field is missing or invalid. details lists each field with its problem.Nothing
401(none)The API key is missing or invalid. The body is { "error": "Unauthorized: Missing or invalid token" }.Nothing
404COMPANY_NOT_FOUNDThe company_id you passed belongs to another account.Nothing
409COMPANY_ALREADY_REGISTEREDThe company_id you passed already has a tax registration.Nothing
409ENVIRONMENT_MISMATCHThe company_id you passed belongs to a different environment than your API key.Nothing
422FINANZAMT_NOT_FOUND / VALIDATION_ERRORNo tax office matches the address, or the dates are out of order.Nothing
409IDEMPOTENCY_REQUEST_IN_PROGRESSA request with the same Idempotency-Key is still running. Retry with the same key.Nothing
422IDEMPOTENCY_KEY_REUSEDThe Idempotency-Key was already used with a different request body.Nothing
422ELSTER_PLAUSIBILITY_ERRORELSTER refuses the registration. details names each field to fix and what ELSTER needs.Nothing
500PROCESSING_ERRORAn error on our side. Contact support with the timestamp.Nothing

Example

Request
{
  "legal_form": "gbr",
  "package": "self",
  "signature_path": "M 10 10 L 90 90 M 90 10 L 10 90",
  "name": "Muster & Partner GbR",
  "purpose": "Grafikdesign und Beratung",
  "operational_activity_start_date": "2025-03-01",
  "founding_date": "2025-03-01",
  "founding_kind": "1",
  "accounting_profit_method": "01",
  "address": {
    "street": "Berger Strasse 45",
    "street_second_line": "2. Etage",
    "zip": "60316",
    "city": "Frankfurt am Main",
    "country": "de"
  },
  "directors": [
    {
      "first_name": "Max",
      "middle_name": "Karl",
      "last_name": "Mustermann",
      "dob": "1985-07-10",
      "address": {
        "street": "Berger Strasse 45",
        "zip": "60316",
        "city": "Frankfurt am Main",
        "country": "de"
      }
    }
  ],
  "shareholders": {
    "individuals": [
      {
        "first_name": "Max",
        "last_name": "Mustermann",
        "dob": "1985-07-10",
        "address": {
          "street": "Berger Strasse 45",
          "zip": "60316",
          "city": "Frankfurt am Main",
          "country": "de"
        },
        "share_percentage": 50
      },
      {
        "first_name": "Erika",
        "last_name": "Musterfrau",
        "dob": "1990-03-22",
        "address": {
          "street": "Berger Strasse 45",
          "zip": "60316",
          "city": "Frankfurt am Main",
          "country": "de"
        },
        "share_percentage": 50
      }
    ],
    "entities": []
  },
  "vat": {
    "accounting_method": "accrual",
    "estimated_balance_type": "payable",
    "estimated_balance_amount": 3000
  },
  "financial_estimates": {
    "formation_year": { "revenue_amount": 40000, "profit_amount": 30000 },
    "following_year": { "revenue_amount": 60000, "profit_amount": 50000 }
  }
}
Response
{
  "response": {
    "result": "success",
    "message": "Tax registration filed with ELSTER.",
    "company_id": "9b2e4c7a-1d3f-4a8b-9c6e-2f5a7b8c1d0e",
    "tax_registration_id": "450506c1-d1a7-46e2-aca6-41a816805595",
    "status": "submitted",
    "tax_office": { "number": "2614", "name": "Frankfurt am Main" },
    "transfer_ticket": "et1a2b3c4d5e6f7a8b9c0d1e2f3a4b5c6d",
    "documents": {
      "questionnaire_url": "https://app.beglaubigt.de/download?bucket=company-documents&id=3f1c2b9e-7d4a-4c1e-9b2f-5a8d6e7f9c0b&token=a1H...To5",
      "confirmation_url": "https://app.beglaubigt.de/download?bucket=company-documents&id=8a2d4e6f-1b3c-4d5e-8f9a-0b1c2d3e4f5a&token=b2J...Up6"
    },
    "timestamp": "2025-02-01T07:19:30.443Z"
  }
}

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