diff --git a/sqlite_utils/db.py b/sqlite_utils/db.py
index da06238..e97f71d 100644
--- a/sqlite_utils/db.py
+++ b/sqlite_utils/db.py
@@ -961,7 +961,7 @@ class Table:
                     else:
                         raise
                 self.last_rowid = result.lastrowid
-                self.last_pk = None
+                self.last_pk = self.last_rowid
                 # self.last_rowid will be 0 if a "INSERT OR IGNORE" happened
                 if (hash_id or pk) and self.last_rowid:
                     row = list(self.rows_where("rowid = ?", [self.last_rowid]))[0]
diff --git a/tests/test_update.py b/tests/test_update.py
new file mode 100644
index 0000000..0b99333
--- /dev/null
+++ b/tests/test_update.py
@@ -0,0 +1,24 @@
+import pytest
+
+
+def test_update_rowid_table(fresh_db):
+    table = fresh_db["table"]
+    rowid = table.insert({"foo": "bar"}).last_pk
+    table.update(rowid, {"foo": "baz"})
+    assert [{"foo": "baz"}] == list(table.rows)
+
+
+def test_update_pk_table(fresh_db):
+    table = fresh_db["table"]
+    pk = table.insert({"foo": "bar", "id": 5}, pk="id").last_pk
+    assert 5 == pk
+    table.update(pk, {"foo": "baz"})
+    assert [{"id": 5, "foo": "baz"}] == list(table.rows)
+
+
+def test_update_compound_pk_table(fresh_db):
+    table = fresh_db["table"]
+    pk = table.insert({"id1": 5, "id2": 3, "v": 1}, pk=("id1", "id2")).last_pk
+    assert (5, 3) == pk
+    table.update(pk, {"v": 2})
+    assert [{"id1": 5, "id2": 3, "v": 2}] == list(table.rows)