The deposit came in; the reference doesn't say whose it is
Online registration for a workshop, a course or a team-building day gets stuck where the money moves: a payment request goes out, the transfer's reference is incomplete, the invoice is made by hand, and when someone cancels nobody knows how much is due back. What to look for if you'd hand registration, payment and invoicing to one system.
- Written by
- Kristóf Karner — independent developer, Budapest
- Updated
- 7 November 2026
Where the manual round gets stuck
The reference. You have to work out from the transfer who paid. If the reference is missing, or the money arrives under another name because a company pays for the participant, matching it up is handwork, and easy to get wrong.
Between the payment request and the invoice. A payment request isn't an invoice: once the money is in, the real invoice or receipt still has to be issued. If that happens in a batch in the evening, sooner or later one gets missed, and the participant asks for it.
The full session. If registrations come by email, two people can sign up for the last place. One of them has to be told they didn't get in after all, and if they've already paid, the money has to go back.
The team-building day. A company signs up ten people, asks for a single invoice in its own name, with its VAT number, and the participants' names only come later. Over email that's several rounds.
The cancellation. Without a written rule, every cancellation is a negotiation, and the refund is more handwork. Besides your own cancellation rule, a consumer may also have the 14-day right of withdrawal; there is an exception for leisure events tied to a date, but not always for courses — worth checking with a lawyer.
What to look for if you'd hand it to a system
- Sessions with a number of places, closing by themselves when they're full.
- Signing up one person or several, as a private person or a company, with the invoice details.
- Card payment at sign-up, and an invoice straight after it, not a payment request.
- A written cancellation rule, and a cancelling or correcting invoice with the refund.
- A confirmation and a reminder for the participant, and a participant list for you.
- Who stores the participants' details, and when they are deleted.
- Whether it runs on your own domain, with your site's look, and whether it puts a cookie on the visitor.
A deposit or the full fee
The simplest is for the participant to pay the full fee at sign-up and get the invoice straight away. Many places ask for a deposit, but that's an accounting question too: for a VAT-registered business in Hungary, VAT on a deposit is due when it's received, and if a company pays it or the participant asks, it needs an advance invoice; the final invoice then settles it. If the rest is paid on the spot, the final invoice comes from your own till or invoicing tool, and the two have to match. Before asking for a deposit online, ask your accountant how you should invoice it.
Ready-made or your own
There are ready-made services for ticketing and registration, with a monthly fee or a commission. If the answer to everything on the list above is yes, and you don't mind registration running on the provider's site and under its brand, they can be a good choice. Your own pays off if it has to run on your domain, issue company invoices too, and follow your cancellation rule exactly.
What I build
I build systems like this as a custom offer, after an assessment. The base exists: my own booking page (confirmation, reminders, cancelling, protection against abuse), and Hungarian invoices issued automatically from card payments, which I use in other systems of mine. How the booking page was built is in the Workshop piece, and connecting payments with invoices in the piece on invoicing.
If you run workshops, courses or team-building days, write me an email: how many sessions you have a month, for how many places, and how people sign up with you. From that I'll tell you what can be handed to a system, even if it's a ready-made tool.
kristof@kristofkarner.comQuestions on the topic
How can online registration be connected to payment and invoicing?
With card payment at sign-up, and an invoice issued automatically after the payment. Then there is no payment request and no matching of references: the invoice is made together with the payment, from the participant's details.
Can I ask for a deposit online?
Yes, but it's an accounting question too: for a VAT-registered business in Hungary, VAT on a deposit is due when it's received, and if a company pays it or the participant asks, it needs an advance invoice; the final invoice then settles it. Agree with your accountant first how you invoice it.
How can a company sign up several people?
In a good system, with a single registration: the number of participants and the company's invoice details, VAT number included. The participants' names can come later; the invoice is one, in the company's name.
What can I do if the transfer's reference doesn't say who paid?
By hand, you can match it by the amount, the date and the sender's name, and if that isn't enough, you have to ask back. If payment is tied to the registration, no reference is needed: the system knows who paid and for what.