Click the "Security" link on that very page. https://squareup.com/help/en-us/article/5144-square-cash-security https://squareup.com/help/en-us/article/5144-squ

Click the "Security" link on that very page. https://squareup.com/help/en-us/article/5144-square-cash-security https://squareup.com/help/en-us/article/5144-square-cash-sec... If you use an app, they sign the mails. If you use regular e-mail, you have to confirm the transfer, which means simply spoofing a mail from you won't work.