diff --git a/cmd/dump/dump_integration_test.go b/cmd/dump/dump_integration_test.go
index 7b2b72f5..3e43f190 100644
--- a/cmd/dump/dump_integration_test.go
+++ b/cmd/dump/dump_integration_test.go
@@ -75,6 +75,13 @@ func TestDumpCommand_Issue83ExplicitConstraintName(t *testing.T) {
 	runExactMatchTest(t, "issue_83_explicit_constraint_name")
 }
 
+func TestDumpCommand_Issue91ColDefaultExpr(t *testing.T) {
+	if testing.Short() {
+		t.Skip("Skipping integration test in short mode")
+	}
+	runExactMatchTest(t, "issue_91_col_default_expr")
+}
+
 func runExactMatchTest(t *testing.T, testDataDir string) {
 	runExactMatchTestWithContext(t, context.Background(), testDataDir)
 }
diff --git a/ir/normalize.go b/ir/normalize.go
index 0f869b1a..26f685c8 100644
--- a/ir/normalize.go
+++ b/ir/normalize.go
@@ -129,10 +129,13 @@ func normalizeDefaultValue(value string) string {
 		}
 		// Pattern: 'G'::schema.type_name -> 'G'
 		// Pattern: 'G'::type_name -> 'G'
+		// More precisely: strip only the ::type_name portion, preserving any content after it
 		if strings.Contains(value, "'::") {
-			if idx := strings.Index(value, "'::"); idx != -1 {
-				value = value[:idx+1]
-			}
+			// Use regex to match and remove type casts after string literals
+			// Pattern: 'string'::type_name -> 'string'
+			// This preserves content after the type cast, e.g., (expr 'val'::type) -> (expr 'val')
+			re := regexp.MustCompile(`'::([a-zA-Z_][a-zA-Z0-9_]*\.)?[a-zA-Z_][a-zA-Z0-9_]*`)
+			value = re.ReplaceAllString(value, "'")
 		}
 	}
 
diff --git a/testdata/dump/issue_91_col_default_expr/manifest.json b/testdata/dump/issue_91_col_default_expr/manifest.json
new file mode 100644
index 00000000..5d26051c
--- /dev/null
+++ b/testdata/dump/issue_91_col_default_expr/manifest.json
@@ -0,0 +1,10 @@
+{
+  "name": "issue_91_default_expr",
+  "description": "Test case for default expression with NOT NULL dumping (GitHub issue #91)",
+  "source": "https://github.com/pgschema/pgschema/issues/91",
+  "notes": [
+    "Tests that complex default expressions with NOT NULL constraints are correctly formatted",
+    "Bug: Missing closing parenthesis when default expression contains parentheses and column has NOT NULL",
+    "Example: DEFAULT (now() AT TIME ZONE 'utc') NOT NULL should not become DEFAULT (now() AT TIME ZONE 'utc' NOT NULL"
+  ]
+}
diff --git a/testdata/dump/issue_91_col_default_expr/pgdump.sql b/testdata/dump/issue_91_col_default_expr/pgdump.sql
new file mode 100644
index 00000000..5e88255e
--- /dev/null
+++ b/testdata/dump/issue_91_col_default_expr/pgdump.sql
@@ -0,0 +1,59 @@
+--
+-- PostgreSQL database dump
+--
+
+-- Dumped from database version 17.5 (Debian 17.5-1.pgdg120+1)
+-- Dumped by pg_dump version 17.5 (Homebrew)
+
+SET statement_timeout = 0;
+SET lock_timeout = 0;
+SET idle_in_transaction_session_timeout = 0;
+SET transaction_timeout = 0;
+SET client_encoding = 'UTF8';
+SET standard_conforming_strings = on;
+SELECT pg_catalog.set_config('search_path', '', false);
+SET check_function_bodies = false;
+SET xmloption = content;
+SET client_min_messages = warning;
+SET row_security = off;
+
+SET default_tablespace = '';
+
+SET default_table_access_method = heap;
+
+--
+-- Name: some_table; Type: TABLE; Schema: public; Owner: -
+--
+
+CREATE TABLE public.some_table (
+    id integer NOT NULL,
+    created_at timestamp without time zone DEFAULT (now() AT TIME ZONE 'utc'::text) NOT NULL
+);
+
+
+--
+-- Name: some_table_id_seq; Type: SEQUENCE; Schema: public; Owner: -
+--
+
+ALTER TABLE public.some_table ALTER COLUMN id ADD GENERATED BY DEFAULT AS IDENTITY (
+    SEQUENCE NAME public.some_table_id_seq
+    START WITH 1
+    INCREMENT BY 1
+    NO MINVALUE
+    NO MAXVALUE
+    CACHE 1
+);
+
+
+--
+-- Name: some_table some_table_pkey; Type: CONSTRAINT; Schema: public; Owner: -
+--
+
+ALTER TABLE ONLY public.some_table
+    ADD CONSTRAINT some_table_pkey PRIMARY KEY (id);
+
+
+--
+-- PostgreSQL database dump complete
+--
+
diff --git a/testdata/dump/issue_91_col_default_expr/pgschema.sql b/testdata/dump/issue_91_col_default_expr/pgschema.sql
new file mode 100644
index 00000000..88686947
--- /dev/null
+++ b/testdata/dump/issue_91_col_default_expr/pgschema.sql
@@ -0,0 +1,18 @@
+--
+-- pgschema database dump
+--
+
+-- Dumped from database version PostgreSQL 17.5
+-- Dumped by pgschema version 1.4.0
+
+
+--
+-- Name: some_table; Type: TABLE; Schema: -; Owner: -
+--
+
+CREATE TABLE IF NOT EXISTS some_table (
+    id integer GENERATED BY DEFAULT AS IDENTITY,
+    created_at timestamp DEFAULT (now() AT TIME ZONE 'utc') NOT NULL,
+    CONSTRAINT some_table_pkey PRIMARY KEY (id)
+);
+
diff --git a/testdata/dump/issue_91_col_default_expr/raw.sql b/testdata/dump/issue_91_col_default_expr/raw.sql
new file mode 100644
index 00000000..095246a9
--- /dev/null
+++ b/testdata/dump/issue_91_col_default_expr/raw.sql
@@ -0,0 +1,23 @@
+--
+-- Test case for GitHub issue #91: Default expression with NOT NULL dumping
+--
+-- This test case reproduces a bug where column default expressions containing
+-- parentheses combined with NOT NULL constraints are formatted incorrectly.
+--
+-- The issue occurs when:
+-- 1. A column has a default expression wrapped in parentheses
+-- 2. The default expression contains complex SQL like `now() AT TIME ZONE 'utc'`
+-- 3. The column also has a NOT NULL constraint
+--
+-- Original bug: DEFAULT (now() AT TIME ZONE 'utc') NOT NULL
+-- Gets corrupted to: DEFAULT (now() AT TIME ZONE 'utc' NOT NULL
+-- (Missing closing parenthesis before NOT NULL!)
+--
+
+--
+-- Test table with complex default expressions
+--
+CREATE TABLE some_table (
+    id serial primary key,
+    created_at timestamp without time zone default (now() at time zone 'utc') not null
+);