For FastBill users

FastBill dunning, automated flat rate instead of per case.

In FastBill, automatic dunning is a paid add-on billed per dunning case — with one payment reminder and up to three dunning letters. DunningHero connects directly to FastBill and duns in up to nine levels, for a monthly price based on how many invoices are overdue at once.

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How your invoice reaches us

  1. FastBill

    keeps invoices and payments

    connected directly
  2. DunningHero

    sends reminders and dunning letters

Nothing is sent until you switch sending on

Connected directly

Connect once, and the invoices arrive by themselves.

DunningHero connects directly to FastBill. No export, no list to upload, nothing typed twice.

Sign-in

Your FastBill email address and an API key — added once, done.

What comes across

Customers, open and overdue invoices and payments.

Always current

Where FastBill reports changes by webhook, an invoice reaches us seconds later — otherwise the regular sync picks it up.

Partial payments, credit notes, cancellations and invoices on payment terms that are not dunned are recognised and handled correctly.

The difference

What FastBill does and what comes after.

One price for the whole chain, not for every case.

  1. 01

    Today in FastBill

    Automatic dunning is a paid add-on, billed per dunning case.

    With DunningHero

    One monthly price by the number of invoices overdue at once — email sending is included in every plan.

  2. 02

    Today in FastBill

    One payment reminder and up to three dunning letters, all deadlines counted from the due date.

    With DunningHero

    Up to six payment reminders and three dunning levels; each level waits after the previous letter for as long as you set.

  3. 03

    Today in FastBill

    Each level goes by email or, with credits, by post.

    With DunningHero

    Email or letter, as an Einwurf-Einschreiben from a level you choose, a text message alongside if you like — and default interest under § 288 BGB as its own line.

GuideCreating and automating dunning letters in FastBill

Read the guide

How it works

Connected in four steps.

  1. 1

    Connect FastBill

    Sign in once or add a key — after that there is nothing left to transfer.

  2. 2

    Invoices arrive

    Open and overdue invoices, customers and payments appear in DunningHero and stay current.

  3. 3

    Set your levels

    Deadlines, texts, channels and fees per level — or take our templates. Free for 14 days.

  4. 4

    Switch sending on

    Nothing goes out before you allow it. Until then you only see what would happen.

Features

What runs by itself from then on.

Up to nine levels

Six payment reminders and three dunning letters, each with its own deadline, wording and tone.

No login needed

The run follows your schedule. You hear from us because something went out — not so that it can.

Payment stops the chain

Once the amount is settled in your accounting system, the next sync ends the escalation.

Text and letter, not just email

As add-ons: a short text message alongside the level and, when needed, a letter we print and post — for customers who overlook email.

Dunning fees and interest

A €5.00 fee per dunning level by default, freely adjustable, never on a payment reminder. Default interest from the day of default — at the consumer rate or, via a setting, the business rate.

Pause instead of switching off

Pause a single invoice or a whole customer — one click, with the reason kept in the audit trail.

Pricing

Priced by overdue invoices in flight.

Not per seat, not per revenue. Annual billing is 15% cheaper.

PlanIn parallelPrice / monthChoose plan
Free5 overdue invoices€0.00/ month
Start10 overdue invoices€9.00/ month
Start10 overdue invoices€19.00/ month
BusinessRecommended50 overdue invoices€19.00/ month
Business50 overdue invoices€39.00/ month
Pro250 overdue invoices€39.00/ month
Pro250 overdue invoices€69.00/ month
Enterprise750 overdue invoices€59.00/ month
Enterprise750 overdue invoices€99.00/ month
40

Recommended: Business

  • 14 days free, no card
  • No setup fee
  • Monthly plans cancel monthly
  • All prices net, plus VAT.

FAQ

Questions from FastBill users.

See everything DunningHero does
Do I need FastBill's dunning add-on for this?
No. DunningHero reads open invoices directly from FastBill. If you already use the FastBill add-on, switch it off for these invoices so no customer is dunned twice.
How does DunningHero charge?
By the number of invoices overdue at the same time — not per dunning case and not per seat. The plans are further up this page, and the first 14 days are free.
Does DunningHero notice when a payment arrives in FastBill?
Yes. Once the invoice is paid in FastBill, the next sync ends the chain. Partial payments, credit notes and cancellations are recognised too.

Sources

Statements about FastBill follow the vendor's public pages, last checked in September 2026. Something out of date? Tell us and we will correct it.

FastBill is a trademark of its respective owner. DunningHero is not affiliated with or endorsed by FastBill.

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FastBill automatic dunning: flat rate, not per case | DunningHero