So, for in-person transactions, any surcharge (at least for VIsa) over 3% should be reported (or any on debit or prepaid cards). Please submit and as I have said Visa does investigate (sometimes with undercover transactions), but doesn't close the loop with the complaint.

Visa complaint form:
https://usa.visa.com/contact-us.html

Their internal material:
https://usa.visa.com/content/dam/VCO...quirements.pdf
https://usa.visa.com/content/dam/VCO...qa-for-web.pdf

Mastercard is still at 4%: https://www.mastercard.us/en-us/busi...rge-rules.html

Now, for online transactions, I see most of this surcharge nonsense on small sites that essentially take a "fee". This is different than surcharge because for many sites, they charge that fee regardless of how you pay (ACH, card, etc.). If you see a lower fee rate for non-credit (debit or ACH), that lower fee is where the 3 (or 4)% count, it is NOT a card surcharge otherwise.