Yes, we highly recommend linking a savings account instead of checking account. Once you have connected your EARN account to your bank, we check to see if your savings are growing by $20 each month. If you connect your checking account, you may not be able to consistently increase the total monthly balance by $20 each month because of the need to constantly make withdraws from the checking account. (See post: Withdrawals)
This is why we strongly encourage you to connect a savings account. For example, if you take $300 out for a car payment, $7 for coffee, $73 for your cell phone bill, you would need to add $380 + $20 back in before the end of the program month to earn your monthly rewards. If your EARN account is showing a negative balance it is because you have made more withdrawals than deposits. Checking accounts make it harder to earn rewards.