diff --git a/docs/message_retention_policies.md b/docs/message_retention_policies.md
index 78055b2f64b22e236d27f0db295bfb254c7e060b..72f08fbb4c4a8f480887a785fdc1916065d70ffc 100644
--- a/docs/message_retention_policies.md
+++ b/docs/message_retention_policies.md
@@ -185,7 +185,7 @@ host. However, even though the database engine won't free up the disk
 space, it will start writing new data into where the purged data was.
 
 If you want to reclaim the freed disk space anyway and return it to the
-operating system, the server admin needs to run `VACUUM FULL;` on the
-database (see the related
+operating system, the server admin needs to run `VACUUM FULL;` (or
+`VACUUM;` for SQLite databases) on Synapse's database (see the related
 [PostgreSQL documentation](https://www.postgresql.org/docs/current/sql-vacuum.html)).