Google Pay is considered to be at least as secure as other payment services. Because of its connection with a Google account, though, there is a higher risk if your data is stolen: Unauthorized users now not only have access to your money that’s linked to Google Pay, but also to your e-mails in Gmail and your Google Drive. The more services you use with your Google account, the more important it is to protect your login data.
But, after all: Google Pay hides all important credit card information as soon as you enter it. Only the last four digits of the card number or provider are shown in the browser and app. Google promises that information on credit cards and accounts is encrypted and stored on secure servers. Google also states that suspicious actions are detected and accounts are protected from fraud and phishing in regard to the data protection check.
In 2012, a security breach was closed relatively quickly by Google. The discovery was of a loophole that allowed hackers to steal credit card information during payment transactions via the NFC function. In recent years, there have been no negative reports about the security of Google Wallet (or Google Pay). You should always be aware, though, that entering credit card or account information comes with a slight risk. If you use payment services such as Google Pay on a computer or smartphone, then you need to have an antivirus program or firewall installed to adequately protect yourself against data misuse (e.g. keyloggers).