diff --git a/CHANGES.txt b/CHANGES.txt
index 57b6aa3559..4015caa7da 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -9,6 +9,7 @@
  * Add java.base/java.lang.reflect among opens for jvm11-client.options (CASSANDRA-19780)
 Merged from 4.1:
 Merged from 4.0:
+ * Emit error when altering a table with non-frozen UDTs with nested non-frozen collections the same way as done upon table creation (CASSANDRA-19925)
  * Safer handling of out-of-range tokens (CASSANDRA-13704)
  * Fix memory leak in BTree.FastBuilder (CASSANDRA-19785)
  * Fix millisecond and microsecond precision for commit log replay (CASSANDRA-19448)
diff --git a/src/java/org/apache/cassandra/cql3/statements/schema/AlterTableStatement.java b/src/java/org/apache/cassandra/cql3/statements/schema/AlterTableStatement.java
index fc0b4cffe6..5f37acf09b 100644
--- a/src/java/org/apache/cassandra/cql3/statements/schema/AlterTableStatement.java
+++ b/src/java/org/apache/cassandra/cql3/statements/schema/AlterTableStatement.java
@@ -48,6 +48,7 @@ import org.apache.cassandra.db.Keyspace;
 import org.apache.cassandra.db.guardrails.Guardrails;
 import org.apache.cassandra.db.marshal.AbstractType;
 
+import org.apache.cassandra.db.marshal.UserType;
 import org.apache.cassandra.exceptions.InvalidRequestException;
 import org.apache.cassandra.gms.ApplicationState;
 import org.apache.cassandra.gms.Gossiper;
@@ -314,6 +315,16 @@ public abstract class AlterTableStatement extends AlterSchemaStatement
             if (isStatic && table.clusteringColumns().isEmpty())
                 throw ire("Static columns are only useful (and thus allowed) if the table has at least one clustering column");
 
+            // check for nested non-frozen UDTs or collections in a non-frozen UDT
+            if (type.isUDT() && type.isMultiCell())
+            {
+                for (AbstractType<?> fieldType : ((UserType) type).fieldTypes())
+                {
+                    if (fieldType.isMultiCell())
+                        throw ire("Non-frozen UDTs with nested non-frozen collections are not supported for column " + column.name);
+                }
+            }
+
             ColumnMetadata droppedColumn = table.getDroppedColumn(name.bytes);
             if (null != droppedColumn)
             {
diff --git a/test/unit/org/apache/cassandra/cql3/validation/entities/UserTypesTest.java b/test/unit/org/apache/cassandra/cql3/validation/entities/UserTypesTest.java
index 9ad6aeb047..7a1d73ea37 100644
--- a/test/unit/org/apache/cassandra/cql3/validation/entities/UserTypesTest.java
+++ b/test/unit/org/apache/cassandra/cql3/validation/entities/UserTypesTest.java
@@ -183,6 +183,11 @@ public class UserTypesTest extends CQLTester
         String myType2 = KEYSPACE + '.' + typename2;
         assertInvalidMessage("Non-frozen UDTs with nested non-frozen collections are not supported",
                 "CREATE TABLE " + KEYSPACE + ".wrong (k int PRIMARY KEY, v " + myType2 + ")");
+
+        String userType = createType("CREATE TYPE %s (userids SET<UUID>)");
+        createTable("CREATE TABLE %s (id int PRIMARY KEY)");
+        assertInvalidMessage("Non-frozen UDTs with nested non-frozen collections are not supported for column my_type",
+                             "alter TABLE %s add my_type " + userType);
     }
 
     @Test