Reg II Debit Interchange: The Reset Is the Real Risk

The real Reg II risk for card issuers isn't the court fight everyone's watching over the past week.

A fresh round of amicus briefs just hit the Sixth Circuit in Linney's Pizza, the challenge to the Fed's debit interchange cap. Last week I covered where the Visa/Mastercard settlement stands. Same debit story, different front. And the court fight, for all the attention it's pulling, isn't the part you should be planning around.

The Fed's 2023 proposal to lower the debit interchange cap still isn't final, and it's unlikely to move while Reg II is being relitigated. A North Dakota court vacated the existing rule but stayed its own ruling pending appeal, so the cap is still in effect today. A Kentucky court then upheld the same rule, creating a clean split. The major bank and credit union trade groups have stopped asking for more time and are now pushing the Fed to withdraw the proposal outright.

So the timing is genuinely uncertain. But timing isn't the part worth focusing on.

The headline everyone grabs is the base component dropping from 21 cents to 14.4, about a 31% cut. Worth being precise here: that's the base, not the full cap. On a $50 ticket the total maximum fee falls from roughly 24.5 cents to 17.7, closer to 28%. Either way, a real hit for covered issuers.

But the cut isn't the story. The mechanism is.

The proposal hard-wires a reset every two years, updating all three components off the latest covered-issuer cost data, without reopening a fresh comment cycle each time. And those reported processing costs have fallen hard. Fed staff have noted they've nearly halved since the original rule. So it behaves less like a one-time haircut and more like a formula with a built-in downward bias. If costs keep drifting lower, the cap follows them, and pricing mechanisms like this are historically sticky once they're in place.

That's the part covered issuers should be modeling. Not "what happens if the cap goes to 14.4," but "what does our debit P&L look like after three or four reset cycles."

And if you're under $10 billion, don't assume the exemption insulates you. The legal cap doesn't apply, but exempt pricing still moves in a market shaped by the regulated benchmark, network competition, and merchant routing leverage. ABA's data points to exempt interchange falling around 35% from 2011 to 2022, even though the cap never legally touched those issuers, because networks anchor exempt schedules to the regulated tier with a lag.

Layer on the Fed's clarification that Reg II's routing requirements apply to card-not-present debit, which gives acquirers more room to steer online volume to the cheaper network, and the multi-year picture gets less comfortable than the headline cut suggests.

The litigation is the gating event. The reset formula is the planning issue. The issuers who come out ahead won't be the ones who treated the cap as a one-year shock. They'll be the ones who modeled it as a recurring line item to manage through pricing, routing, and product mix.