Migrate existing contracts from your own system

Business Case

If you already dipped your toe into subscriptions you might already provide some services on a recurring basis and handle the billing manually, or with a system not built for this purpose. As you are convinced by our Nitrobox solution, you now wonder how to get your existing subscriptions into Nitrobox, given they have already been billed party through their contract term.

Feature: Billing Start Date

When creating a contract you can now specify a Contract "Billing Start Date" when using Expert mode, which indicates the point of migration from when NBX will take over billing. The "Billing Start Date" indicates the point in time when you need Nitrobox to take over the billing for your existing subscription. As of this specified date, Nitrobox sets up the billing periods and invoices your subscription. Please note that you can only specify the billing-start date once for your contract!

Note: Usages and additional Line Items you transfer to our system will be billed regardless at this point. The Billing Start Date only affects automatic recurring and one-time billing configured via our Options.


Say you offer a 1-year subscription, billed for 10€ at the start of the month. Your first customers signed on the 1st of January and received the first 10€ invoice on that very day. Now more and more customers sign up and handling all these invoices proofs is too expensive so you sign up with Nitrobox and want us to start billing in June.

To do so simply set up the plan in Nitrobox as you defined them with your customers and create the contracts, setting the contract start date to whenever they signed up and Contract Billing Start Date in May, which will lead to us creating invoices in June.

Edge Cases to consider

  1. Given the example above you can also set the Billing Start Date to the 1st of June and achieve the same result. With this behavior, we want to prevent errors when people set the date to the very first day of the billing period as they "know" when the first invoice in NBX should be created.
  2. Using the example we gave above, invoices were created at the start of the billing period. If your setup issues invoices at the end of a billing period instead, the otherwise same setup would result in the first NBX invoice to be created on June 30th (as we take over billing for the June billing period), so if you would like the system to create the May invoice as well you would have to set the Contract Billing Start Date in April.
  3. We will still bill any line items or usages that you send to our system, even if they are from before the Billing Start Date!


Q: If I cancel a Contract or terminate it to a date before the Billing Start Date will Nitrobox issue credit notes for the past periods as well?
A: Nitrobox will only issue credit notes of invoices it has initially billed. It will not create a credit note for an Invoice it is not aware of.