Are letter boxes as thin as royal mail small parcel

In the UK, Royal Mail's standard letterbox size is typically around 170mm (6.7 inches) wide, 100mm (3.9 inches) high, and 50mm (2 inches) deep. This is the standard size for most residential letterboxes.

However, Royal Mail's small parcel size, also known as a "small parcel" or "satchel", is slightly larger. The dimensions for a Royal Mail small parcel are:

As you can see, the small parcel size is slightly larger than the standard letterbox size. But, to answer your question, letterboxes are generally not as thin as Royal Mail's small parcel size.

In fact, most letterboxes are designed to accommodate standard A4-sized letters and small packages, which are typically around 210mm (8.3 inches) wide and 297mm (11.7 inches) long. So, while letterboxes may vary in size, they are generally thicker and wider than Royal Mail's small parcel size.

It's worth noting that some modern letterboxes, especially those designed for urban areas or high-rise buildings, may be smaller and more compact to accommodate the increasing use of online shopping and smaller packages. However, even these smaller letterboxes are typically still wider and thicker than Royal Mail's small parcel size.