Is it legal to charge 3% for use of credit card?

Could you please clarify for me, is it indeed considered legal to impose a 3% surcharge on customers who choose to utilize credit cards for their transactions? This query stems from a desire to ensure compliance with all relevant financial regulations and consumer protection laws. Furthermore, I'm interested in understanding if such a practice aligns with industry standards or if it might potentially deter consumers from utilizing credit card payment options. Additionally, could you elaborate on any potential legal implications or consequences that might arise as a result of implementing such a fee? Thank you for your insight.