[10][11] Square provides e-Commerce and inventory capabilities,[12][2] customer appointments,[13] payroll processing, shift scheduling, and access to banking and business loans.

[14][15] As of 2024, Square is available in the U.S., Australia, Canada, France, Japan, Republic of Ireland, Spain and the U.K.[16] The inspiration for Square occurred to Jack Dorsey in 2009, when his friend Jim McKelvey was unable to complete a $2,000 sale of his glass faucets and fittings because he could not accept credit cards.

[17][18] In December 2009, Dorsey announced the launch of Square, which allowed merchants and individuals to accept secure payment from credit and other cards using a mobile phone and a "card-reading dongle".

[22] In August 2012, Starbucks announced it would use Square to process transactions with customers who pay via debit or credit card.

[24] In May 2013, Block announced that its Square service was available in Japan after agreeing to a partnership with Sumitomo Mitsui Card Corporation.

[27] In February 2014, Whole Foods Market announced it would use Square Register at select stores' sandwich counters, pizzerias and coffee, juice, wine and beer bars.

[35] In the same year, Square launched a reader for Android and iOS that accepts contactless and chip card payments.

[40] In August 2018, Square released a version of its magstripe reader with a Lightning connector, allowing it to be used on iPhones without a headphone jack.

[7] According to the company, its "larger business customers", identified by Square as generating more than $500,000 in annualized gross payment volume (GPV), made up 40% of its seller base in the third quarter of 2022.

[48] On September 7-8, 2023, Square experienced a 14-hour long outage that left businesses unable to process customers' payments.

The service recommended vendors switch to an offline mode to mitigate the issue, where the payments get processed once the network connectivity is re-established but were met with mixed results.

Several days later, Square it was determined that the disruption was caused due to a misconfiguration in the Domain Naming System (DNS).

The original version consisted of a read head directly wired to a 3.5 mm audio jack, through which unencrypted, analog card information was fed to smartphones for amplification and digitization.

[22] Square Reader is Payment Card Industry Data Security Standard (PCI) compliant and Verisign certified.

[36] Square Terminal features a display, prints receipts, and accepts chip, swipe, and contactless payments.

[25] In June 2019, The Wall Street Journal reported that Square inadvertently sent transaction receipts to the wrong email address, leading to adverse consequences such as outing one woman's impending divorce.

As the parent company is governed by US laws, the bank would have been subject with charges of trafficking in prohibited Cuban goods if it had processed the fund transactions.

Square received criticism from affected merchants due to the opaque nature of the process, its suddenness, and difficulties in appealing the designation.