There are a few reasons why choosing a business credit card that doesn't affect your personal credit score is a good idea.
Less credit utilization
Signing up for a business credit card that won't report your company activities on your personal credit has its advantages. If you anticipate high spending, separating business and personal credit can keep your personal credit score from taking a dive due to high credit utilization. Since the balances you have on a business credit card won't display on your personal credit report, you won't see significant dips in your score if you have to make major purchases for your business.
No late payments shown
If you have cash flow issues and miss a business card payment, you won't have to worry about a late payment mark on your personal credit report. Keep in mind that late payment may not make its way on your personal credit report. Still, American Express, Capital One and Chase may report more serious activities such as a business card delinquency on your personal credit file.
Credit card companies that check your personal credit may not report its activity but could still show the account on your personal credit file. This could be an advantage because the age of the account and the credit limit can boost your credit score without the negatives of payment history.