diff --git a/doc/snac.5 b/doc/snac.5
index ac16625..5720cd3 100644
--- a/doc/snac.5
+++ b/doc/snac.5
@@ -89,6 +89,10 @@ has the user id as name and contains the following subdirectories and files:
 .Bl -tag -width tenletters
 .It Pa user.json
 User configuration file.
+.It Pa user_o.json
+User configuration override file. This file is intended for administrators to
+override some user preferences (e.g. for setting shorter purge days that what
+the user may have defined).
 .It Pa key.json
 Secret/public key PEM data.
 .It Pa followers.idx