If there's no money currently IN the Paypal from a previous transfer, then yes, you need a card associated with it so Paypal can automatically charge/transfer from the bank/credit account associated with the card.

The only way to make Paypal an instant transfer when purchasing things are either a) money already in the account (the paypal account, not your checking account), or b) having a card linked to Paypal. Linking just a checking account via account and routing numbers still aren't instant. The card must be in there for it to be instant (again, unless there is already money sitting in the  Paypal funds).

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