Post Office – Newton Stewart, Wigtown – Opening Hours & Branch Details Post Office is easy to get to at 27 South Main Street, approximately a 6.60 mile drive south from the centre of Newton Stewart (not far from North Main St and Southfield Park). This branch is an important addition to the areas of Bladnoch, Loch Head, Kirkinner, Wigtown, Carsluith and Kirvennie. 6:00 am until 5:30 pm are its hours of business today (Friday). Read the specifics on this page for Post Office Newton Stewart, Wigtown, including the hours of operation, address, contact number and more.