How long does it take online payment to post on my Sam's credit card?

Online payments to a Sam's Club credit card made with an electronic check are immediately debited from the checking account used, according to Sam's Club. Payments made this way are posted to the account the same day.

To make a payment, the credit card holder must input her account and routing number, driver's license number and birthdate. Sam's Club customers must register their credit card accounts to be able to pay online. Card holders can also pay their bills in person at any Sam's Club or Wal-Mart, including at the checkout cash registers. Payments made this way are also posted to the account the same day, as Sam's Club points out.