How ticket size changes which plan wins
The same two quotes can flip which is cheaper based on nothing but your average sale size.
The same two plans can flip which one is cheaper depending on nothing but your average ticket size — the typical dollar amount of a single sale. A coffee shop and a furniture store can be quoted identical terms and land on opposite answers.
Why ticket size matters, not just volume
Both flat-rate and interchange-plus plans cost you a percentage of the sale plus a fixed fee per transaction. For a given amount of monthly volume, a low average ticket means more individual transactions, and a high average ticket means fewer, larger ones. That changes how much the fixed per-transaction fee matters relative to the percentage:
- Low ticket, high transaction count: the fixed fee gets charged far more often, so it dominates the bill. Whichever plan has the lower per-transaction fee tends to win.
- High ticket, low transaction count: the fixed fee is charged rarely, so the percentage rate dominates instead. Whichever plan has the lower percentage tends to win.
Notice that your total monthly volume doesn't appear in that logic. It isn't irrelevant — more volume means whichever plan wins does so by a bigger dollar amount — but it doesn't change which plan wins. That's decided by the ticket size and the two plans' terms alone.
The crossover point
Because of that, there's usually a specific average ticket — a break-even point — where the two plans cost exactly the same, and the winner swaps on either side of it. Here's a worked, hypothetical example to show the mechanism, not real market rates:
Hypothetical: a plan with a lower fixed fee vs. one with a lower rate
| Plan | Rate | Per-transaction fee |
|---|---|---|
| Plan A | 2.60% | $0.10 |
| Plan B | 1.80% | $0.25 |
At a $10 average ticket, Plan A costs $0.36 per sale and Plan B costs $0.43 — Plan A wins, because its small fixed fee barely adds up. At a $100 average ticket, Plan A costs $2.70 and Plan B costs $2.05 — Plan B wins, because its lower rate now matters more than its bigger fixed fee. The two plans cost the same at an average ticket of $18.75; below it, Plan A is cheaper, above it, Plan B is cheaper.
In practice, either structure can end up as "Plan A" or "Plan B" — it depends entirely on the specific rate and per-transaction fee you're quoted, which is why this isn't a rule of thumb you can apply blindly.
Use your own numbers
The calculator computes this break-even ticket automatically from the card mix and the flat-rate and interchange-plus terms you enter. Your monthly volume is not part of that calculation, for the reason given above — it cancels out — so changing it moves the dollar amounts without moving the crossover.
Look for the break-even ticket line under the results. It reads one of two ways. A dollar figure means the two plans do cross: below that ticket size one is cheaper, above it the other is. The words "no crossover at these terms" mean they never cross — one plan is cheaper at every ticket size, and no change to your average sale flips it. That is a common enough answer that it is the one the calculator's own starting numbers produce.
When there is a crossover and your average ticket sits well on one side of it, that's a reasonable signal of which structure suits you; if it sits close to it, the two plans are genuinely close and the decision may come down to terms this calculator doesn't model, like monthly minimums or statement fees — see reading a processing statement for those.