An anonymous survey collects nothing that ties a response to a person, while a confidential survey does link your response to your employee record and then restricts who can see it and at what level of detail. Lattice puts the split in one line: "Anonymous means you don't know who said what. Confidential means you know who said it, but you're not going to disclose that information" [4]. Almost every engagement and pulse product sold to employers sits on the confidential side, because that link is what makes it possible to break results out by department, tenure, manager, and location.
Vendors often say anonymous and mean confidential
Culture Amp is unusually direct about this. Its documentation states that Culture Amp surveys "are not anonymous" and that "We prefer to communicate that Culture Amp surveys are 'Confidential'" [1]. In its attributed format, "Each response is linked to an employee in your account through the users profile" [1]. Microsoft Viva Glint runs two survey classes, confidential and identifiable, with a different response threshold on each [8].
What each type means for you in practice
Under a confidential setup the tool knows the answer came from you, so your protection is a reporting rule rather than an absence of data. Culture Amp's participant guide states "We do not display individual responses" and explains that people with access to results can only see demographic groups meeting the reporting minimum set for the survey [2]. That works well inside a group of any real size, and less well on a five person team or in a filter combination that only one person matches.
A genuinely anonymous survey is recognizable from the moment you open it. Culture Amp describes its unattributed format as one where responses have "no connection to any specific individual" [1], which means no personalized link, no name prefilled, no reminder singling you out, and no demographic fields beyond the ones you type yourself. Technical anonymity also depends on the platform discarding network metadata, which is a setting rather than a default in general purpose survey tools [10][11].