Time to get your Statements out!! You should have received these in the mail by now. In the last paragraph on the last page of your statement is where they usually disclose (hide) the rate increase. It may be a % the rate is going up and/or a transaction fee ($.xx) increase. It also states that if you continue to process with the company May 1st you have agreed to their rate increase.
It may be time to shop around for a different Merchant Services Provider if your current company is raising your rates. There are plenty of Merchant Services Providers out there that are not increasing their processing rates.
I'm frightened at the number of payment processing business model business owners or those in charge of the books for companies, who don't even bother opening their statements anymore! This industry is very broken and a lot of the processors have made their statements so confusing and hard to read, that business owners quit opening them. This gives these companies a real easy way to raise rates and fees since all the alerts and communications are on the statements.