diff --git a/BirthdayBot/BackgroundServices/StaleDataCleaner.vb b/BirthdayBot/BackgroundServices/StaleDataCleaner.vb
index 1bdc2cb..eb22f95 100644
--- a/BirthdayBot/BackgroundServices/StaleDataCleaner.vb
+++ b/BirthdayBot/BackgroundServices/StaleDataCleaner.vb
@@ -1,5 +1,4 @@
-Imports Npgsql
-''' <summary>
+''' <summary>
 ''' Automatically removes database information for guilds that have not been accessed in a long time.
 ''' </summary>
 Class StaleDataCleaner
@@ -10,29 +9,66 @@ Class StaleDataCleaner
     End Sub
 
     Public Overrides Async Function OnTick() As Task
-        Using db = Await BotInstance.Config.DatabaseSettings.OpenConnectionAsync()
-            ' Update only for all guilds the bot has cached
-            Using c = db.CreateCommand()
-                c.CommandText = $"update {GuildStateInformation.BackingTable} set last_seen = now() " +
-                    "where guild_id = @Gid"
-                Dim updateGuild = c.Parameters.Add("@Gid", NpgsqlTypes.NpgsqlDbType.Bigint)
-                c.Prepare()
+        ' Build a list of all values to update
+        Dim updateList As New Dictionary(Of ULong, List(Of ULong))
+        For Each gi In BotInstance.GuildCache
+            Dim existingUsers As New List(Of ULong)()
+            updateList(gi.Key) = existingUsers
 
-                Dim list As New List(Of ULong)(BotInstance.GuildCache.Keys)
-                For Each id In list
-                    updateGuild.Value = CLng(id)
-                    c.ExecuteNonQuery()
+            Dim guild = BotInstance.DiscordClient.GetGuild(gi.Key)
+            If guild Is Nothing Then Continue For ' Have cache without being in guild. Unlikely, but...
+
+            ' Get IDs of cached users which are currently in the guild
+            Dim cachedUserIds = From cu In gi.Value.Users Select cu.UserId
+            Dim guildUserIds = From gu In guild.Users Select gu.Id
+            Dim existingCachedIds = cachedUserIds.Intersect(guildUserIds)
+            existingUsers.AddRange(existingCachedIds)
+        Next
+
+        Using db = Await BotInstance.Config.DatabaseSettings.OpenConnectionAsync()
+            ' Prepare to update a lot of last-seen values
+            Dim cUpdateGuild = db.CreateCommand()
+            cUpdateGuild.CommandText = $"update {GuildStateInformation.BackingTable} set last_seen = now() " +
+                "where guild_id = @Gid"
+            Dim pUpdateG = cUpdateGuild.Parameters.Add("@Gid", NpgsqlTypes.NpgsqlDbType.Bigint)
+            cUpdateGuild.Prepare()
+
+            Dim cUpdateGuildUser = db.CreateCommand()
+            cUpdateGuildUser.CommandText = $"update {GuildUserSettings.BackingTable} set last_seen = now() " +
+                "where guild_id = @Gid and user_id = @Uid"
+            Dim pUpdateGU_g = cUpdateGuildUser.Parameters.Add("@Gid", NpgsqlTypes.NpgsqlDbType.Bigint)
+            Dim pUpdateGU_u = cUpdateGuildUser.Parameters.Add("@Uid", NpgsqlTypes.NpgsqlDbType.Bigint)
+            cUpdateGuildUser.Prepare()
+
+            ' Do actual updates
+            For Each item In updateList
+                Dim guild = item.Key
+                Dim userlist = item.Value
+
+                pUpdateG.Value = CLng(guild)
+                cUpdateGuild.ExecuteNonQuery()
+
+                pUpdateGU_g.Value = CLng(guild)
+                For Each userid In userlist
+                    pUpdateGU_u.Value = CLng(userid)
+                    cUpdateGuildUser.ExecuteNonQuery()
                 Next
-            End Using
+            Next
 
             ' Delete all old values - expects referencing tables to have 'on delete cascade'
             Using t = db.BeginTransaction()
                 Using c = db.CreateCommand()
-                    ' Delete data for guilds not seen in 2 weeks
+                    ' Delete data for guilds not seen in 4 weeks
                     c.CommandText = $"delete from {GuildStateInformation.BackingTable} where (now() - interval '28 days') > last_seen"
                     Dim r = c.ExecuteNonQuery()
                     If r <> 0 Then Log($"Removed {r} stale guild(s).")
                 End Using
+                Using c = db.CreateCommand()
+                    ' Delete data for users not seen in 8 weeks
+                    c.CommandText = $"delete from {GuildUserSettings.BackingTable} where (now() - interval '56 days') > last_seen"
+                    Dim r = c.ExecuteNonQuery()
+                    If r <> 0 Then Log($"Removed {r} stale user(s).")
+                End Using
             End Using
         End Using
     End Function
diff --git a/BirthdayBot/Data/GuildUserSettings.vb b/BirthdayBot/Data/GuildUserSettings.vb
index 173c666..45ca57b 100644
--- a/BirthdayBot/Data/GuildUserSettings.vb
+++ b/BirthdayBot/Data/GuildUserSettings.vb
@@ -130,6 +130,7 @@ Class GuildUserSettings
                 "birth_month integer not null, " +
                 "birth_day integer not null, " +
                 "time_zone text null, " +
+                "last_seen timestamptz not null default NOW(), " +
                 "PRIMARY KEY (guild_id, user_id)" +
                 ")"
             c.ExecuteNonQuery()