US Post Office is located at 210 W Front St, Monroe, MI. This business specializes in Post Offices. US Post Office is open Mon, 7:59am-5:05pm; Tue, 7:59am-5:05pm; Wed, 7:59am-5:05pm; Thu, 7:59am-5:05pm; Fri, 7:59am-5:05pm; Sat, Closed; Sun, Closed and accepts American Express, Discover and Visa.