Almost 28,000 pillboxes were built but now it is estimated only about 20% remain and many of these are in a poor condition. There may only be 1000 left in good condition. The great majority have been destroyed, a process that started even before the end of the war. Ditches and trenches have been filled; loopholes repaired; wood and metal re-cycled.In addition to receiving compensation, farmers whose land was used to build the structures were paid after the war to fill in ditches and trenches and to demolish pillboxes.
The basic designs were adapted to local circumstances and available building materials such that, outwardly, two pillboxes of the same basic design could look quite different. The height of a pillbox could vary significantly according to local needs: some were half buried so that the embrasures might be as low as ground level, others were raised up to give a better view; those built into hillsides might lack embrasures on some walls; the entrance could be moved and its size varied as might be convenient and there may be additional walls to protect the entrance, a freestanding blast wall or a steel door.
Soldiers would be stationed inside and armed with rifles and machine guns; the structures would often be camouflaged to maximise the element of surprise. The type 28 is the only one with a specific anti-tank capability.For many pillboxes, a new use has been found.
The type 28s, being internally spacious and having a large rear entrance, are probably the most amenable to reuse and on farms and in gardens they serve as cattle sheds and storage lockers. Other, more imaginative pillbox applications recorded include use as a pub cellar, a conversion to a ladies toilet and an open-air theatre box office. Some pillboxes have been converted to make roosts for bats. Pillboxes that are well dug-in and thick walled are naturally damp and provide a stable thermal environment that is required by bats that would otherwise hibernate in caves.