Breach date: 2025-09-01. Added to this index: 2025-10-16. Accounts affected: about 18M. Domain: prosper.com.
What happened
In September 2025, Prosper announced that it had detected unauthorised access to their systems, which resulted in the exposure of customer and applicant information. The data breach impacted 17.6M unique email addresses, along with other customer information, including US Social Security numbers. Prosper advised that they did not find any evidence of unauthorised access to customer accounts and funds, and that their customer-facing operations were uninterrupted. Further information about the incident is contained in Prosper's FAQs.
Breach data sourced from Have I Been Pwned, used under CC BY 4.0. Additional breach metadata provided by XposedOrNot. DataExposed is an independent service and is not affiliated with or endorsed by either.
What was exposed
Browser user agent details: A short text string your browser sends to every website, naming the browser, its version, the operating system and often the device type, for example Chrome on Windows or Safari on an iPhone.
Credit status information: Details from a credit file or lender record, such as open accounts, credit limits, missed payments, defaults, bankruptcies, hardship arrangements and recent credit enquiries.
Dates of birth: Your full birth date, day, month and year, collected at signup for age checks, identity verification, insurance quotes, birthday offers or government services.
Email addresses: The email address you used to register or log in. It is the most common field in breaches because it doubles as your username on most sites.
Employment statuses: A field showing whether you are employed, self-employed, unemployed, a student or retired, collected by lenders, insurers, job sites, government services and marketing surveys.
Government issued IDs: Numbers or images of official identity documents, such as passports, national identity cards, Social Security numbers, Medicare cards, tax file numbers, residence permits and voter cards.
Income levels: An estimated or self-reported household or personal income band, collected by surveys, lenders, retailers, dating apps and marketing databases.
IP addresses: The network addresses your devices used when you signed up, logged in or posted, recorded by almost every website in its access logs.
Names: Your first name, surname and sometimes middle name or initials, as you gave them when you signed up. It appears in almost every breach because nearly every account asks for it.
Physical addresses: Your residential, postal, billing or delivery address, stored by retailers, utilities, banks, government services and almost any company that sends you something.
What to do now
Check whether your own address is in this dataset with the free email breach check.
Review the accounts connected to this service and turn on two-factor authentication.
Turn on two-factor authentication on your email account first, because it is the reset path for everything else.
Treat calls and messages that quote real details about you as hostile until you verify them another way.
Frequently asked questions
What data was leaked in the Prosper breach?
The Prosper breach exposed Browser user agent details, Credit status information, Dates of birth, Email addresses, Employment statuses, Government issued IDs, Income levels, IP addresses, Names, Physical addresses. About 18M accounts were affected.
Was I affected by the Prosper breach?
Run the free email breach check with the address you used on that service. It will tell you whether your address appears in this dataset.
What should I do about the Prosper breach?
Treat any message that quotes details from this breach as suspicious, turn on two-factor authentication, and consider removing your details from people-search sites if your address or phone was included.