Integrate FastBill with MailChimp to automate workflows, sync data between apps, and eliminate repetitive tasks with AI-powered automation.
Start from a real workflow other teams are already running.
FastBill
When this happens...
New Offer
New Customer
Customer Updated
Customer Deleted
New Invoice
Invoice Completed
Invoice Canceled
Offer Updated
New Contact
Contact Updated
Contact Deleted
MailChimp
Automatically do this!
Add Note to Subscriber
Add Subscriber to Tag
Update Subscriber
Archive Subscriber
Create Campaign
Create Custom Event
Remove Subscriber from Tag
Permanently Delete Subscriber
Find Campaign by ID
Find Subscriber by Email
Send Campaign
Find Customer
Add Tags to Audience Member
Find Tag
Get Campaign Reports
List Stores
Create Store Customer
List Audiences
Add Merge Field
List Products
List customers
List Carts
Add Contact to Audience
Add Note to Subscriber in MailChimp when New Offer in FastBill
Use this flowAdd Subscriber to Tag in MailChimp when New Offer in FastBill
Use this flowUpdate Subscriber in MailChimp when New Offer in FastBill
Use this flowArchive Subscriber in MailChimp when New Offer in FastBill
Use this flowCreate Campaign in MailChimp when New Offer in FastBill
Use this flowCreate Custom Event in MailChimp when New Offer in FastBill
Use this flowRemove Subscriber from Tag in MailChimp when New Offer in FastBill
Use this flowPermanently Delete Subscriber from MailChimp when New Offer in FastBill
Use this flowFind Campaign by ID in MailChimp when New Offer in FastBill
Use this flowFind Subscriber by Email in MailChimp when New Offer in FastBill
Use this flowEverything you can automate between FastBill and MailChimp.
When this happensTriggers
A trigger is an event that starts a workflow.
Triggers when a new offer was created within your FastBill account.
Triggers when a new customer is created within your FastBill account.
Triggers when a customer is updated within your FastBill account.
Triggers when a customer is deleted within your FastBill account.
Triggers when a new invoice is created within your FastBill account.
Triggers when an invoice is completed within your FastBill account.
Action is the task that follows automatically within your FastBill integrations.
Creates a new customer in FastBill.
Creates a new invoice.
Adds full payment for an invoice.
Send an invoice by email.
Creates a revenue entry.
Adds full payment for a revenue.

Follow a simple walkthrough to create, test, and launch your first automation.
Connect your apps
Link the apps you want to automate.
Configure your workflow
Set up triggers, actions, and map your data.
Test & publish
Test your workflow and publish it.
Recognized by leading review platforms and trusted by 10,000+ businesses worldwide.
Just describe the task in plain English. viaSocket AI selects the right apps, builds the workflow, maps the fields, and prepares everything for review before you publish.
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FastBill is a cloud app for German invoicing & accounting. Writing offers and invoices, paying your bills or preparing your tax return is easier than ever with FastBill.
Learn moreMailchimp is an all-in-one marketing platform that helps businesses manage and talk to their clients, customers, and other interested parties.
Learn moreSign up for a free viaSocket account, then authorize both your FastBill and MailChimp accounts. From there, pick a trigger in one app and an action in the other. Your first workflow can be live in under five minutes.
Yes. viaSocket uses instant triggers where available, so data moves between FastBill and MailChimp as soon as the event happens. Scheduled polling triggers run at a maximum interval of 15 minutes.
Yes. You can map specific fields, apply filters to skip records that do not match your conditions, and transform values before they reach MailChimp. No coding required.
Yes. You can set up a workflow where FastBill triggers actions in MailChimp, and a separate workflow where MailChimp triggers actions in FastBill. Both run independently and in real time.
viaSocket logs every run so you can see exactly what succeeded and what failed. Failed tasks can be retried from the dashboard without re-configuring the workflow.
Yes, there is a free plan that covers basic workflows between FastBill and MailChimp. Paid plans unlock higher task limits, faster polling, and advanced features like multi-step workflows and conditional logic.
No. The entire FastBill and MailChimp integration is built through a visual, point-and-click interface. Code blocks are available if you want them, but they are never required.