Square's free 'Square Cash' service allows users to send money via email

Rolling out on Tuesday, Square Cash is a simple and free one-step digital solution for sending money person-to-person.

Unlike its familiar square-shaped credit card swiper that enables small businesses to easily and economically accept credit card payments, Square's new product involves no hardware beyond a user's computer, smartphone or tablet. The only requirements to use Square Cash are a valid Visa or MasterCard debit card and an email address.

To send cash to a friend, a user creates an email with the recipient's name in the "To" field, "cash@square.com" in the "CC" field, and the amount to be sent in the subject line. A note can also be included in the email's body, but this step is optional.

Square Cash will receive the email, check that the bank account linked to the sender's email address has the requisite funds, and send along the payment to the recipient. Upon accepting the payment, the money will be placed in a recipient's linked account and becomes available for withdrawal in one to two business days.

For first time users, Square Cash will send an email to both sender and recipient with steps to link their respective debit card accounts with the service. After this one-time setup, no further action is necessary.

Currently, transfer values are capped at $250 per week for the basic service, which can be raised to $2,500 with a few additional steps. While still free, the higher dollar amount requires users send Square their name, date of birth and last four digits of their social security number. Alternatively, a Facebook login can be used for verification.

As an alternative to emailing money, Square Cash also has an iOS app that can be downloaded for free from the App Store.

Currently, the service is only available to U.S. residents, though the company plans to expand operations internationally with a for-pay service.