diff --git a/doc/src/sgml/logical-replication.sgml b/doc/src/sgml/logical-replication.sgml
index 2edf65af66e..efbed7b3bcb 100644
--- a/doc/src/sgml/logical-replication.sgml
+++ b/doc/src/sgml/logical-replication.sgml
@@ -1803,6 +1803,13 @@ Included in publications:
    configuration.
   </para>
 
+  <note>
+   <para>
+    Sequence synchronization requires the publisher to be running
+    <productname>PostgreSQL</productname> 19 or later.
+   </para>
+  </note>
+
   <sect2 id="sequence-definition-mismatches">
    <title>Sequence Definition Mismatches</title>
    <para>
@@ -2353,7 +2360,16 @@ CONTEXT:  processing remote data for replication origin "pg_16395" during "INSER
      <command>ALTER SUBSCRIPTION ... REFRESH SEQUENCES</command></link>
      or by copying the current data from the publisher (perhaps using
      <command>pg_dump</command>) or by determining a sufficiently high value
-     from the tables themselves.
+     from the tables themselves.  Note that
+     <link linkend="sql-altersubscription-params-refresh-sequences">
+     <command>ALTER SUBSCRIPTION ... REFRESH SEQUENCES</command></link> only
+     re-synchronizes sequences that are already known to the subscription
+     (see <xref linkend="logical-replication-sequences"/>); in particular, it
+     requires the publisher to be running <productname>PostgreSQL</productname>
+     19 or later. Before relying on it to prepare for a switchover or
+     failover, confirm that the publisher's version supports sequence
+     replication and that the sequences of interest are already known to the
+     subscription.
     </para>
    </listitem>
 
diff --git a/doc/src/sgml/ref/alter_subscription.sgml b/doc/src/sgml/ref/alter_subscription.sgml
index 51081ef369e..ec6d5f1dcf6 100644
--- a/doc/src/sgml/ref/alter_subscription.sgml
+++ b/doc/src/sgml/ref/alter_subscription.sgml
@@ -245,6 +245,12 @@ ALTER SUBSCRIPTION <replaceable class="parameter">name</replaceable> RENAME TO <
       sequences are subscribed. Run <literal>REFRESH PUBLICATION</literal>
       first if the publication's set of sequences has changed.
      </para>
+     <note>
+      <para>
+       Sequence replication requires the publisher to be running
+       <productname>PostgreSQL</productname> 19 or later.
+      </para>
+     </note>
      <para>
       See <xref linkend="sequence-definition-mismatches"/> for
       recommendations on how to handle any warnings about sequence definition
diff --git a/src/backend/commands/subscriptioncmds.c b/src/backend/commands/subscriptioncmds.c
index a2c079fcb5a..de62ec49514 100644
--- a/src/backend/commands/subscriptioncmds.c
+++ b/src/backend/commands/subscriptioncmds.c
@@ -1322,6 +1322,16 @@ AlterSubscription_refresh_seq(Subscription *sub)
 	/* The publisher connection is only needed for the origin check. */
 	PG_TRY();
 	{
+		/*
+		 * Sequence synchronization depends on publisher-side functionality
+		 * introduced in PostgreSQL 19, so it cannot work against an older
+		 * publisher.
+		 */
+		if (walrcv_server_version(wrconn) < 190000)
+			ereport(ERROR,
+					errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+					errmsg("cannot synchronize sequences if the publisher is running a version earlier than PostgreSQL 19"));
+
 		check_publications_origin_sequences(wrconn, sub->publications, true,
 											sub->origin, NULL, 0, sub->name);
 	}
diff --git a/src/backend/replication/logical/sequencesync.c b/src/backend/replication/logical/sequencesync.c
index 82f503f1c00..06946afe683 100644
--- a/src/backend/replication/logical/sequencesync.c
+++ b/src/backend/replication/logical/sequencesync.c
@@ -444,6 +444,16 @@ copy_sequences(WalReceiverConn *conn)
 	StringInfoData cmd;
 	MemoryContext oldctx;
 
+	/*
+	 * Sequence synchronization depends on publisher-side functionality
+	 * introduced in PostgreSQL 19, so it cannot work against an older
+	 * publisher.
+	 */
+	if (walrcv_server_version(conn) < 190000)
+		ereport(ERROR,
+				errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				errmsg("cannot synchronize sequences if the publisher is running a version earlier than PostgreSQL 19"));
+
 	initStringInfo(&seqstr);
 	initStringInfo(&cmd);