diff --git a/basis/lists/lists-tests.factor b/basis/lists/lists-tests.factor
index 866ac0f597..d9b6fbd5d9 100644
--- a/basis/lists/lists-tests.factor
+++ b/basis/lists/lists-tests.factor
@@ -48,3 +48,7 @@ IN: lists.tests
 ] unit-test
 
 { { 1 } { 2 } } [ { 1 2 } sequence>list 1 lcut [ list>array ] bi@ ] unit-test
+
+{ { { 1 } { { 2 } } } } [
+    1 nil cons 2 nil cons nil cons nil cons cons deeplist>array
+] unit-test
diff --git a/basis/lists/lists.factor b/basis/lists/lists.factor
index 1b106b0002..0efb182864 100644
--- a/basis/lists/lists.factor
+++ b/basis/lists/lists.factor
@@ -93,6 +93,9 @@ PRIVATE>
 : list>array ( list -- array )
     [ ] lmap>array ;
 
+: deeplist>array ( list -- array )
+    [ dup list? [ deeplist>array ] when ] lmap>array ;
+
 INSTANCE: cons-state list
 INSTANCE: +nil+ list