diff --git a/crates/api_common/src/community.rs b/crates/api_common/src/community.rs
index 1f4a9463..8801f67f 100644
--- a/crates/api_common/src/community.rs
+++ b/crates/api_common/src/community.rs
@@ -97,6 +97,9 @@ pub struct BanFromCommunity {
   pub ban: bool,
   pub remove_data: Option<bool>,
   pub reason: Option<String>,
+  /// A time that the ban will expire, in unix epoch seconds.
+  ///
+  /// An i64 unix timestamp is used for a simpler API client implementation.
   pub expires: Option<i64>,
 }
 
diff --git a/crates/api_common/src/person.rs b/crates/api_common/src/person.rs
index 328674e1..af24a84c 100644
--- a/crates/api_common/src/person.rs
+++ b/crates/api_common/src/person.rs
@@ -214,6 +214,9 @@ pub struct BanPerson {
   /// Optionally remove all their data. Useful for new troll accounts.
   pub remove_data: Option<bool>,
   pub reason: Option<String>,
+  /// A time that the ban will expire, in unix epoch seconds.
+  ///
+  /// An i64 unix timestamp is used for a simpler API client implementation.
   pub expires: Option<i64>,
 }