diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 84dbee0c41..d3947139c0 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -7888,11 +7888,26 @@ ATPrepAlterColumnType(List **wqueue,
 										  COERCE_IMPLICIT_CAST,
 										  -1);
 		if (transform == NULL)
-			ereport(ERROR,
-					(errcode(ERRCODE_DATATYPE_MISMATCH),
-			  errmsg("column \"%s\" cannot be cast automatically to type %s",
-					 colName, format_type_be(targettype)),
-					 errhint("Specify a USING expression to perform the conversion.")));
+		{
+			/* error text depends on whether USING was specified or not */
+			if (def->cooked_default != NULL)
+				ereport(ERROR,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("result of USING clause for column \"%s\""
+								" cannot be cast automatically to type %s",
+								colName, format_type_be(targettype)),
+						 errhint("You might need to add an explicit cast.")));
+			else
+				ereport(ERROR,
+						(errcode(ERRCODE_DATATYPE_MISMATCH),
+						 errmsg("column \"%s\" cannot be cast automatically to type %s",
+								colName, format_type_be(targettype)),
+				/* translator: USING is SQL, don't translate it */
+					   errhint("You might need to specify \"USING %s::%s\".",
+							   quote_identifier(colName),
+							   format_type_with_typemod(targettype,
+														targettypmod))));
+		}
 
 		/* Fix collations after all else */
 		assign_expr_collations(pstate, transform);
diff --git a/src/test/regress/expected/alter_table.out b/src/test/regress/expected/alter_table.out
index 65274bc26b..3ad2c55775 100644
--- a/src/test/regress/expected/alter_table.out
+++ b/src/test/regress/expected/alter_table.out
@@ -1665,7 +1665,7 @@ select f3,max(f1) from foo group by f3;
 -- Simple tests for alter table column type
 alter table foo alter f1 TYPE integer; -- fails
 ERROR:  column "f1" cannot be cast automatically to type integer
-HINT:  Specify a USING expression to perform the conversion.
+HINT:  You might need to specify "USING f1::integer".
 alter table foo alter f1 TYPE varchar(10);
 create table anothertab (atcol1 serial8, atcol2 boolean,
 	constraint anothertab_chk check (atcol1 <= 3));
@@ -1680,7 +1680,10 @@ select * from anothertab;
 
 alter table anothertab alter column atcol1 type boolean; -- fails
 ERROR:  column "atcol1" cannot be cast automatically to type boolean
-HINT:  Specify a USING expression to perform the conversion.
+HINT:  You might need to specify "USING atcol1::boolean".
+alter table anothertab alter column atcol1 type boolean using atcol1::int; -- fails
+ERROR:  result of USING clause for column "atcol1" cannot be cast automatically to type boolean
+HINT:  You might need to add an explicit cast.
 alter table anothertab alter column atcol1 type integer;
 select * from anothertab;
  atcol1 | atcol2 
diff --git a/src/test/regress/sql/alter_table.sql b/src/test/regress/sql/alter_table.sql
index b5ee7b087d..29c1875d2e 100644
--- a/src/test/regress/sql/alter_table.sql
+++ b/src/test/regress/sql/alter_table.sql
@@ -1175,6 +1175,7 @@ insert into anothertab (atcol1, atcol2) values (default, false);
 select * from anothertab;
 
 alter table anothertab alter column atcol1 type boolean; -- fails
+alter table anothertab alter column atcol1 type boolean using atcol1::int; -- fails
 alter table anothertab alter column atcol1 type integer;
 
 select * from anothertab;