Per-registrant and percentage pricing rise with your attendance and your ticket price, while a flat licence costs the same whether the event grows or shrinks. Which is cheaper depends entirely on your own numbers, so the only reliable method is to model both against the attendance you expect.
Neither model is wrong. Per-registrant pricing shares the risk, because a small year costs less. A flat licence rewards growth and punishes a bad year. Knowing which way your event is heading tells you which risk you would prefer to carry.
How each model behaves
A per-registrant fee is a fixed amount for each registration. It ignores the ticket price, so it weighs heaviest on low-priced tickets such as student or single-day passes.
A percentage fee takes a share of each ticket. It scales with both attendance and price, so raising your ticket price raises your software bill even though the platform is doing the same work. Some platforms combine the two, and some let you pass the fee to the attendee, which moves the cost but does not remove it.
A flat licence is an annual or per-event sum, sometimes with attendance bands. Check where the bands are. A licence with a cap just below your expected attendance is not really flat.
Who counts as a registrant
This is where modelled costs and real invoices part company. Ask, in writing:
- Are complimentary registrations charged, and at what rate?
- Do speakers, staff, press and volunteers count?
- Do exhibitor staff badges count, and who pays for them, you or the exhibitor?
- Are cancelled and refunded registrations still charged?
- Are transfers and substitutions charged as new registrations?
- Do add-ons such as workshops or dinner tickets count as separate registrations?
- Is there a minimum fee per event regardless of attendance?
For a trade show with a lot of exhibitor staff and invited guests, the unpaid badges can be a meaningful share of the total count. If they are charged, your fee per paying attendee is higher than the headline rate.
Modelling both against your own attendance
Take three scenarios: a poor year, the expected year and a strong year. For each, write down paid registrations by ticket type and unpaid registrations by category.
As an illustration only, suppose 800 paid registrations at an average of 400 dollars, and a fee of 3 percent plus 2 dollars per registration. The percentage comes to 9,600 and the fixed part to 1,600, so 11,200 for the event. Add 300 complimentary badges charged at 2 dollars each and it becomes 11,800. Now compare that with the flat quote. These figures are invented, so use your own.
Our registration and ticketing bill calculator does the per-ticket arithmetic and shows yearly and three-year totals. It is a free calculator and knows nothing about any vendor's prices, only what you type in.
Payment processing is separate either way
Card processing is charged by the payment processor on every transaction, whichever registration model you choose, and whether the software is rented or owned. Some platforms bundle it into one rate and some show it separately. When comparing, strip processing out of every quote so you are comparing software with software.
If the numbers point away from per-registrant pricing
For a growing event, there can come a size where the platform fee is large for the part of the platform you use: a form, ticket types, confirmation emails, badges and a report. Our guide to owning your software discusses when that justifies a build and when a flat licence from a vendor is the simpler answer. Hiro rebuilds the parts of a registration platform an organiser really uses, around the payment processor, for one flat monthly price. The page for conference and trade show organisers explains more.