The short answer
Move to interchange-plus when monthly volume passes roughly $15,000, or sooner if your average ticket exceeds $100, or immediately if you take commercial cards. Below $10,000 monthly with small tickets, a clean flat rate with no monthly fees often costs less overall.
Why average ticket matters
Per-transaction fees dominate small tickets. At a $9 average, ten cents per item is 1.1% before any percentage applies, so the structure with the lower per-item fee wins regardless of the percentage.
Why B2B is different
Commercial and purchasing cards carry higher interchange but qualify for reductions when Level II and III data is passed. Only interchange-plus lets that reduction reach you.
Key takeaways
- $15,000 monthly is the typical crossover
- Large tickets move it lower, tiny tickets move it higher
- Any commercial card volume argues for interchange-plus immediately
Want this checked against your own statement?
We are an independent agent — we shop every processor we work with and bring you the best deal for your profile. Free analysis, every fee named, back within 4 hours. Or call now and we will quote you on the phone.