According to a statement by Square, the invoices system allows business owners to "create, customise and issue" invoices directly from their phone or desktop.
"Invoices are emailed directly to customers, who can then select to pay online securely with Visa, MasterCard or American Express credit or debit cards," said the statement.
Square country head Ben Pfisterer said Australian businesses experience some of the "slowest invoice payment speeds in the world".
"Research shows us that over $19 billion is locked away in outstanding invoices owed to businesses, and with 90 per cent of small business failures a result of poor cash flow, we’re proud to bring tools to Australian sellers to ensure they’ve got every way to get paid," Mr Pfisterer said.
"From accepting card payments with Square Reader to now accepting payments online with Square Invoices, we’re empowering businesses with every tool they need to get paid fast and spend less time on time-consuming operational tasks like generating manual invoices and chasing payments," he said.
Square was founded in 2009 and is headquartered in San Francisco.