Google Checkout is an online payment processing service provided by Google aimed at simplifying the process of paying for online purchases. Users store their credit or debit card and shipping information in their Google Account, so that they can purchase at participating stores by clicking an on-screen button. Google Checkout provides fraud protection and a unified page for tracking purchases and their status.

Google Checkout service became available in the United States on June 28, 2006, and in the UK on April 13, 2007. It was free for merchants until February 1, 2008. From then until May 5, 2009 Google charged US merchants 2.0% plus $0.20 per transaction, and UK merchants 1.4% + £0.20. Google since moved to a tiered cost structure, identical to that of PayPal. Also since this date, Google has discontinued its offer whereby merchants who advertised with an AdWords account were not charged fees on monthly transactions totaling less than ten times their monthly AdWords expenditure.

Google Checkout used to have a program which allowed US IRS Certified 501(c)3 Non-Profit organizations to collect donations online without being charged the standard fee (2.9% + $0.30 per transaction under $3,000 monthly income, with lower rates for larger volumes.