Turn the SOKA-BAU Online-Service into an API

What you can build on SOKA-BAU

• Get open Klärfälle

  Build this

  Reads the Klärfälle tile in the Arbeitgeber-Onlineservice for one Betriebskontonummer (company account number), including the tab In Klärung bei SOKA-BAU.

  Takes

  Betriebskontonummer

  Returns

  Count for you, count with SOKA-BAU, and per Klärfall: employee, report month, what needs correcting, who handles it

• Get employees' Urlaubsansprüche

  Build this

  Reads the employee overview in the Arbeitgeber-Onlineservice: each employee's granted and still available holiday entitlement.

  Takes

  Betriebskontonummer, employee (optional)

  Returns

  Employee, granted holiday days, available holiday days

• List Mandanten with Klärfälle

  Build this

  Opens the Betriebskontonummer field in the Arbeitgeber-Onlineservice and lists your Mandanten, marking those with the red warning triangle for Klärfälle.

  Takes

  Only with Klärfälle (optional)

  Returns

  Betriebskontonummer, company name, has Klärfälle

• Request a SOKA-BAU-Bescheinigung

  Build this

  Requests the SOKA-BAU-Bescheinigung that confirms proper participation, for one Betriebskontonummer, in the Kundenportal.

  Takes

  Betriebskontonummer

  Returns

  Betriebskontonummer, request date, confirmation shown

Automate SOKA-BAU with a workflow

A workflow runs your methods as one process, with nobody at the screen. A schedule or a call from your own system starts it, the steps run in order, and the result arrives in your inbox or in the systems you already use.

• New Klärfälle across all Mandanten

  Build this

  Starts

  Every weekday at 7:00

  Step 1

  List your Mandanten and keep those with the Klärfälle warning triangle.

  Step 2

  For each of them, get the open Klärfälle.

  Step 3

  Keep the Klärfälle that were not there on the last run.

  Step 4

  Email you the list, one section per Betriebskontonummer.

• Changed Urlaubsansprüche sent to your payroll system

  Build this

  Starts

  Every month on the 20th at 6:00, after the Meldung deadline on the 15th

  Step 1

  For each Betriebskontonummer, get the employees' Urlaubsansprüche.

  Step 2

  Keep the employees whose figures changed since the last run.

  Step 3

  Post employee, granted and available holiday days to your payroll system's webhook.

• SOKA-BAU-Bescheinigung on request from your system

  Build this

  Starts

  When your system calls the workflow's webhook with a Betriebskontonummer

  Step 1

  Request the SOKA-BAU-Bescheinigung for that Betriebskontonummer.

  Step 2

  Email you the request date and the confirmation the portal showed.

You can run a workflow by hand on every plan, Free included. Schedules and webhook triggers come with the paid plans, from $29 a month.

Once built, one call from your code

Once you have built a method, it is one POST to /v1/runs from your backend, or a tool an AI agent calls over MCP. This is what “Get open Klärfälle” would look like.

curl https://api.fous.com/v1/runs \
  -H "Authorization: Bearer $FOUS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "method": "kundencenter.soka-bau.de/get_open_klaerfaelle",
    "input": {
      "betriebskontonummer": "40012345"
    }
  }'

{
  "status": "completed",
  "data": {
    "betriebskontonummer": "40012345",
    "for_you": 2,
    "with_soka_bau": 1,
    "klaerfaelle": [
      {
        "employee": "Employee 0417",
        "report_month": "2026-10",
        "issue": "Urlaubstage reported without Urlaubsvergütung",
        "handled_by": "Betrieb"
      }
    ]
  }
}

An example with invented data, not a ready-made endpoint. The method exists in your organization once you build it, and its name, inputs and fields follow your request.

SOKA-BAU’s own options

SOKA-BAU takes the monthly reports in through two channels: the Meldungsupload from a certified Baulohn-Programm in the Arbeitgeber-Onlineservice, and the eXTra-Schnittstelle used by Rechenzentren. From January 2027 reports go only from a program certified by SOKA-BAU and the ITSG, through the GKV-Kommunikationsserver. SOKA-BAU's pages describe no API for reading Klärfälle, account data or Urlaubsansprüche.

Read on November 12, 2026: Meldeverfahren gemeinsamer Einrichtungen, Kundenportal für Betriebe, Baulohn-Programm.

Signing in to SOKA-BAU

The Kundenportal asks for your Benutzername and Passwort, then a Bestätigungscode sent to the email address stored for that user, valid for 15 minutes. The code is on by default and can be turned off in your profile. With Fous you sign in once through SOKA-BAU's own sign-in with your own account: the login is sealed with AES-256, the emailed code is handled, and an expired session is signed back in.

Worth knowing

Open Klärfälle hold everything up

While a Klärfall is open, processing of the whole data set pauses and Erstattungen are not paid out. You resolve it on the Klärfälle tile or with a Korrekturmeldung.

The 15th, and corrections overwrite

The Monatsmeldung is due by the 15th of the following month. A second Meldung for the same month replaces the earlier one in every field it fills.

Reporting channels change in January 2027

From January 2027 reports go only from a Baulohn-Programm certified by SOKA-BAU and the ITSG, through the GKV-Kommunikationsserver.

One login for all your Mandanten

A registered Dienstleister picks each Mandant in the Betriebskontonummer field, so a method takes it as an input. Submitting Meldungen needs a user with schreibende Berechtigung.

More in Construction

• BuildingConnected
• LCPtracker
• Procore
• Autodesk Build
• United Rentals Total Control
• Hyphen SupplyPro
• Trimble Unity Construct
• GCPay
• Oracle Textura Payment Management
• Payapps

Other industries: NuORDER, Walmart Seller Center, AQA Centre Services, DTE Energy online account, METRO Online-Kundenkonto, Axis Corporate Internet Banking.