Can you open a merchant account without having a credit score?

You may not qualify for a merchant account per se, due to lack of credit information, however, there are many 3rd party payment processors would would be willing to provide you with credit card processing facilities with a slightly higher acquiring fees. This is the cost of doing business with them in absence of credit history or a low credit score. Search for 3rd party payment processors or high-risk payment processors and you will find 100s of companies willing to do business with you.