Mandatory service fee revealed after payment details
A fictional booking site shows a $40 ticket through search and selection but adds a compulsory $9 service fee only after card details are entered.
Drip pricing and mandatory feesTicket bookingCheckout
This is an original fictional comparison. It depicts no real business and is not a regulator finding, statutory category or legal safe harbour.
Ticket bookingCheckout
Mandatory service fee revealed after payment details
A fictional booking site shows a $40 ticket through search and selection but adds a compulsory $9 service fee only after card details are entered.
Potentially problematicTicket · $40
Ticket · $40. A mandatory $9 service fee appears only after card entry.. Continue to payment. Pay $49
A mandatory $9 service fee appears only after card entry.
Continue to payment
Pay $49
→
Neutral alternativeTicket total · $49
Ticket total · $49. The $40 base amount and $9 compulsory service fee appear together.. Amount affected: $49. Pay $49. Continue to payment. Payable total and selected items, expanded: The summary shows the line items and total before “Pay $49” is activated.
The $40 base amount and $9 compulsory service fee appear together.
Amount affected$49
Pay $49
Continue to payment
Payable total and selected itemsThe summary shows the line items and total before “Pay $49” is activated.
Why the first version can mislead: The final commercial state diverges from the choice represented earlier in the journey. The problematic state records: “A mandatory $9 service fee appears only after card entry.” Review the timing and affirmative selection needed before “Continue to payment” changes price, product or recurring liability. Late disclosure can make the offer appear cheaper and exploit effort already invested in checkout.
What a fairer design does: Show the foreseeable payable total and compulsory fee near the first material price and preserve it throughout the journey.
Show annotated differences (4)
Potentially problematic version
A mandatory $9 service fee appears only after card entry.Why this state matters: The final commercial state diverges from the choice represented earlier in the journey. The problematic state records: “A mandatory $9 service fee appears only after card entry.” Review the timing and affirmative selection needed before “Continue to payment” changes price, product or recurring liability. Late disclosure can make the offer appear cheaper and exploit effort already invested in checkout.
Pay $49Review prompt: Which affirmative action authorises “Continue to payment”, and where is the resulting price, product or recurring state shown before commitment?
Neutral alternative
The $40 base amount and $9 compulsory service fee appear together.Fairer design: Show the foreseeable payable total and compulsory fee near the first material price and preserve it throughout the journey.
Payable total and selected items, expanded: The summary shows the line items and total before “Pay $49” is activated.Review prompt: Compare the basket before and after the action, including total and line items; does the mutation satisfy “A price is displayed before a later charge becomes visible”?
Review questions (3)
Which affirmative action authorises “Continue to payment”, and where is the resulting price, product or recurring state shown before commitment?
Compare the basket before and after the action, including total and line items; does the mutation satisfy “A price is displayed before a later charge becomes visible”?
Which specific affirmative event creates the final commercial state, and could “Optional add-on deliberately selected” explain the observed outcome instead?
Side-by-side ticket booking interface showing “Ticket · $40” and the clearer alternative “Ticket total · $49”.Provenance: Original hypothetical ticket booking example created for this library; no real business, product or interface is depicted.
Complete practice context
How this example relates to Drip pricing and mandatory fees
A mandatory or foreseeable charge is omitted, obscured or revealed only after the user has invested effort in the transaction. This is a design and research taxonomy for learning and evidence review, not a statutory offence label or an automatic finding that an interface is unlawful.
The full guide explains inclusion and exclusion criteria, potential harms, fairer design, evidence questions and separate Australian legal information layers. The example page isolates one scenario so it can be shared and discussed without reproducing the complete library on one page.
A fictional booking flow records a basic fare selection but the final action purchases a premium flexible fare without a new price-and-product confirmation.
