Sell your CS-Cart or Multi-Vendor catalog on OTTO Market: OTTO categories and attributes, EAN-based listing, stock and price sync, order import, shipments with tracking and returns with your own OTTO app credentials.
Tested on 2 buildsUpdated Nov 6, 2026Version 1.0.0CS-Cart, Multi-Vendor 4.17.2 – 4.21.x No core file edits
Built for
OTTO Market Connector: List products by EAN, sync stock and price and import orders and returns from your own OTTO Market seller account1 of 7
What it does
OTTO Market is the marketplace of the German retailer OTTO, open to third-party sellers. If you run a CS-Cart or Multi-Vendor store and want OTTO Market as an additional sales channel, this add-on connects your own seller account to your shop through the OTTO Market API. You create an app in your own OTTO Partner Connect account and enter its credentials; no service partner registration is needed.
How it works
Create an app in OTTO Partner Connect, enter its Client ID and secret on the connection page and test it in sandbox mode first. Map categories and attributes, set markup and stock buffer. The sync uploads products as OTTO tasks, then sends quantity and shipping profile, pushes stock and price and reads the result. Orders are imported once, a CS-Cart shipment creates the OTTO shipment with tracking, returns can be accepted. Failed jobs retry automatically.
Features
Credentials stored encrypted, separate test and live mode, one-click connection test
Job queue with automatic retries and a log with filters and CSV export
Works with cron (command line or secret address), no long requests during checkout
Multi-Vendor: one marketplace account or one account per vendor
Your own OTTO app credentials (Client ID and secret) with OAuth2 client credentials, sandbox and live mode, secrets stored encrypted
Category and attribute mapping from OTTO's category groups, allowed and recommended values, markup and brand per category
Products uploaded by EAN as OTTO update tasks, polled until done, with OTTO's reason for every refused product
Quantity, price and shipping profile with processing time, results read back per SKU
Order import without duplicates: buyer, delivery and invoice address, prices as sold, orders wait until they are processable
Shipments with carrier, tracking number and return tracking key, cancellation of position items, returns accepted from the admin
Optional EU product safety contact (GPSR) sent with listed products
What you get
Package
kv_otto_market-1.0.0.zip, installed through Add-ons → Manage add-ons
Updates & support
12 months included. Download new versions from your account and install them in Add-ons → Manage add-ons or the Upgrade Center.
License
1 production installation. Staging, dev and localhost are free and unlimited. The add-on keeps working after the update period ends. How licensing works
Compatibility
We list only the builds we install and test on. “Tested” means the full test plan was run on that build; “Supported” means the build is inside the supported range and uses the same hooks.
CS-Cart version and edition compatibility
CS-Cart version
CS-Cart
CS-Cart Ultimate
Multi-Vendor
Multi-Vendor Ultimate
4.22 and later
Testing next
Testing next
Testing next
Testing next
4.21.2
Supported
Supported
Supported
Supported
4.20.x
Supported
Supported
Supported
Supported
4.19.x
Supported
Supported
Supported
Supported
4.18.x
Supported
Supported
Supported
Supported
4.17.2
Supported
Supported
Tested
Supported
Before 4.17.2
Not supported
Not supported
Not supported
Not supported
Last tested build: Multi-Vendor 4.17.2, Nov 6, 2026Tested on: Multi-Vendor 4.17.2
Requirements
Platform
CS-Cart and Multi-Vendor 4.17.2 or later
Requirement
Administrator access to the store's admin panel
Requirement
A seller account at OTTO Market with access to OTTO Partner Connect (OPC), and the user right API-Zugriff (API access) for the user who creates the credentials. You use your own account: you do not need to register as a service partner (see "How OTTO access works" below)
Requirement
A cron job on your server (see step 8)
Core changes
None. Hooks and template overrides only
1.0.0
Nov 6, 2026
Latest
Added 7
Initial release: OTTO Market channel built on the shared Marketplace Hub (CS-Cart and Multi-Vendor 4.17.2 to 4.21.x).
Connection to your own OTTO Partner Connect app: OAuth2 client credentials with the scopes of the six interfaces used, sandbox and live mode, secrets stored encrypted, connection test, ship-from address, shipping profile, return carrier and condition, optional product safety (GPSR) contact.
Category mapping from OTTO's category groups (hub ids derived from the German names), attribute mapping with allowed and recommended values, brand ID per category.
Product upload by EAN through the Products v5 API as asynchronous tasks (polled, reason per refused product), then quantity and shipping profile with processing time (Availability v1); stock and price updates with per-SKU results (200 / 207) and price tasks.
Order import from Orders v4 (cursor paging, only processable position items, prices as sold, buyer and addresses, duplicates prevented), status follow, cancellation of position items.
Shipments v1 with carrier, tracking number, ship-from address and return tracking key; Returns v3 listed per order and accepted from the admin.
Job queue with retries and back-off, cron (command line and secret address), log viewer with CSV export; Multi-Vendor: marketplace owner mode or one OTTO account per vendor.
Tested on Multi-Vendor 4.17.2. First release.
Does it work with CS-Cart and Multi-Vendor?
Yes. The add-on supports CS-Cart and Multi-Vendor. In Multi-Vendor the marketplace owner can use one OTTO account for everyone or let each vendor connect their own.
Which CS-Cart versions are supported?
4.17.2 to 4.21.x.
Where are my credentials stored?
In your own database, encrypted. The key is derived from your store's secret in config.php, so a database dump alone does not reveal them. They are never shown again after saving.
Do I have to register as an OTTO service partner?
No. You connect your own seller account: create an app in OTTO Partner Connect (API-Zugriff) and enter its Client ID and Client secret. The service partner registration (free, at servicepartner.otto.market) is for software companies that build apps for many sellers.
Does it work with OTTO's sandbox?
Yes: test mode uses sandbox.api.otto.market with the credentials of a sandbox app. Whether your seller account can create sandbox apps is decided by OTTO; the add-on is tested against a mock server that follows OTTO's published API specifications, not against OTTO's own systems.
Which OTTO APIs does it use?
Products v5, Availability v1 (quantities, delivery information), Orders v4, Shipments v1, Returns v3 and Shipping Profiles v1. Receipts, price reductions, advertising and the returns warehouse are not used in 1.0.
Does it send data to Kavio Labs?
No. The add-on talks to OTTO only. The license check sends your domain name to the Kavio Labs license server once a day (Kavio Labs downloads).
What happens when OTTO is down?
Jobs fail, wait and are retried automatically (5 minutes up to 12 hours). Nothing is lost and nothing is sent twice.
What happens when the license expires?
New work stops (no new documents, rates, syncs or payments). Work already under way is still finished.
How do I get updates?
Install the new package over the old one. See Installation.
Add a released add-on to this order and save 15% on it. It uses the same edition and store domain.
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Buy with confidence
What stands behind your license
Tested builds
This product was tested on these builds. Builds we did not test are not listed.
CS-Cart4.17.2
Multi-Vendor4.17.2
12 months of updates
Updates and support are included in the price. The product keeps working afterwards; renewing is optional.
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