A 2025 audit of 42 US-facing online casino and sportsbook welcome offers found that 26% of users who clicked "claim" abandoned the signup before depositing — and the single biggest reason, cited in 61% of exit surveys, was bonus terms that only appeared at checkout. The offers looked clean on the landing page. The 40x playthrough, the $10 max bet on bonus funds, the 7-day expiry, and the game-weighting table showed up two screens later, after the user had already handed over an email and started a deposit.

That's not a design flaw. It's a conversion strategy, and it's costing operators more than they think.

The Checkout Reveal Is a Churn Engine

The mechanics are predictable. A landing page promises "$2,500 bonus + 200 free spins." The user clicks through, picks a username, and hits the deposit screen. Only then does a terms accordion expand — and the deal changes shape.

In the audited sample, the average gap between the headline offer and the checkout-disclosed offer was substantial:

  • Playthrough: advertised as "35x" on 14 offers that actually applied 35x to deposit + bonus, not bonus alone — an effective 70x on a $100 deposit.
  • Max bet: 31 of 42 offers capped bonus-play wagers at $10 or less, disclosed at checkout on 22 of them.
  • Expiry: 9 offers gave 7 days or fewer to clear, with the clock starting at deposit, not first wager.

A user who does the math at checkout and bails has already been counted as a "signup" in most affiliate and media reports. The 26% figure is the invisible attrition behind inflated funnel numbers.

Why Regulators Are Starting to Notice

The FTC's 2023 "negative option" rulemaking and state-level gaming statutes increasingly treat material terms disclosed late as a deceptive practice, not a marketing quirk. New Jersey's Division of Gaming Enforcement has fined operators for bonus terms buried in linked PDFs. Michigan and Pennsylvania have similar language in their promotional-advertising rules.

The practical exposure isn't the fine. It's the chargeback and complaint volume. In the audit, offers with checkout-only disclosure generated 3.4x the customer-service tickets per 1,000 deposits compared to offers with terms on the landing page. Those tickets cost money, and they precede the withdrawal disputes that trigger regulatory complaints.

The Operators Getting It Right

A minority of the sample — 11 of 42 — put the effective playthrough, max bet, and expiry in the same visual block as the headline number. Their opt-in-to-deposit conversion was 8 points lower on the click, but their 30-day retained deposit rate was 19% higher. Fewer signups, better customers.

That trade is the whole argument. Bonus hunters and casual players both punish surprise terms, just differently: hunters churn immediately, casuals churn after their first withdrawal gets eaten by a max-bet violation they never saw.

What "Clean" Disclosure Looks Like

The compliant pattern is boring and effective: effective playthrough (not nominal), max bet during bonus play, expiry window and start trigger, and contribution percentages for slots vs. table games — all above the fold, in the same font size as the bonus amount. No accordion. No "see full terms" as the only path.

The Open Question

If 26% of opt-ins die at checkout, how many never opt in at all because they've been burned before? The audit can't measure the users who saw a "$2,500 bonus" headline, assumed the terms were hostile, and never clicked. That's the larger number, and it's the one operators keep choosing not to see.

Players should treat any bonus that hides its playthrough until the deposit screen as a signal, not a formality — and check the max-bet clause before wagering a dollar, because that's the term that voids the most withdrawals.