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C24

C24

APIGoogle SheetsMCP (Claude, Codex)
  • 5 minutes setup. No complicated steps
  • Multiple daily refreshes
  • Developer friendly API docs
Connect bank

Only €5 per account / month

Money back guarantee

read-only · PSD2 · EUR

How to connect C24

Connecting your C24 account to Zenith takes a few minutes, over a secure read-only connection.

Step 1

Create an account

Sign up for Zenith — it takes less than a minute.

Step 1 of bank connection: enter your business details in the Zenith setup form including company name, VAT ID, address, and country.
Step 2

Find your bank

Choose your country, then C24.

Connect your bank — select your bank and country to continue
Step 3

Connect your bank account

We send you to your bank's own login page, where you approve access.

  • You log in with your online or mobile banking
  • Follow the bank's prompts; access is read-only for transactions.
Step 3 of bank connection: securely authenticate with your bank's PSD2 service; Zenith only receives read-only transaction data and never stores your credentials.
Step 4

Back to Zenith

After login we bring you back automatically. Your balance shows as soon as the account is connected.

Step 4 of bank connection: your bank account is securely connected and Zenith shows your total balance, accounts connected, available transaction history, and a first look at your synced expenses.
Step 5

Set up payment

The connection costs just €5 per bank account per month.

Step 5 of bank connection: set up your Zenith billing account, confirm your company details, and add a payment method to start syncing.
Step 6

Transactions start arriving

Within minutes your first transactions appear in Zenith.

  • We refresh the data several times a day
  • Most banks allow up to four refreshes a day
Step 6 of bank connection: transactions start flowing into the Zenith cashflow dashboard with multi-account balance history and real-time cash-in, cash-out insights.
Step 7

Choose where your data goes

Send your data to the tools you already use.

  • Sync with Google Sheets
  • Access via API (clean JSON)
  • MCP connector for Claude or Codex
Step 7 of bank connection: choose where your data goes — API, Google Sheets, or Claude and Codex via the Zenith MCP server.

Specifics

BIC/SWIFT
DEFFDEFF
Transaction history
90 days

Maximum number of days Zenith can access transactions from the moment of connection onward.

The end customer needs to enter his mobile phone number associated with his C24 bank account as psuID and his online banking PIN as psu_password. Doing so successfully will trigger the decoupled SCA.

Supported account types

Business accountsPersonal accountsCorporate accounts

C24 is a bank operating in Germany. With Zenith you connect your C24 account over regulated open banking (PSD2) — read-only — and stream transactions to Google Sheets, your app, or Claude, reconciled in EUR.

For developers

From token to transactions in two calls.

A read-only REST API over plain HTTPS + JSON. Bank transactions, expenses, partners, bank accounts, balances and yearly report aggregates — predictable schema, cursor-friendly filters, and a machine-readable OpenAPI contract.

quickstart.sh
# Base URL
https://hub.zenith-books.com/api/public/v1

# 1. Who am I? (verifies your credentials)
curl https://hub.zenith-books.com/api/public/v1/me \
  -H "Authorization: Bearer zth_live_…" \
  -H "X-Company-Key: <company key>"

# 2. Last month's bank transactions
curl "https://hub.zenith-books.com/api/public/v1/transactions?date_from=2026-06-01&date_to=2026-06-30" \
  -H "Authorization: Bearer zth_live_…" \
  -H "X-Company-Key: <company key>"

# Also available: /expenses, /partners, /bank-accounts,
# /bank-accounts/{id}/balances, /reports/yearly-summary
Connect bankRead the API docs →
FAQ

Before you connect.

Yes, via open banking (PSD2). But direct access needs a special licence and certificate, which is complex and slow. With Zenith you skip all that — reach your transactions via API, Google Sheets, Claude (MCP) or CSV. What connecting directly actually requires

How to connect C24

Connect bank