| Attribute | Description |
 | A Word of Mouth (WOM) box. The clues are distributed somewhere other than online, such as via e-mail, postal mail, or delivered in person. |
 | A snow friendly box is rather a squishy concept. Some people might consider a box that requires several miles of cross-country travel using snow shoes or skies as snow 'friendly,' while other may not. Other boxes might be quite findable if there's an inch or two of snow on the ground but may no longer be easily found if there's a foot or two of snow on the ground. In theory, though, a snow friendly box is one in which important landmarks in the clue would not be covered, nor will digging through layers of snow be required to find the box. |
 | A pet friendly letterbox is located in an area that allows pets to roam, usually with a leash requirement. |
 | This image marks letterboxes that require a compass in order to find. The lack of this picture means the clue doesn't require a compass OR that the creator of the letterbox did not specify a compass requirement. It's generally a good idea to always carry a compass in your letterboxing kit, though, so you'll always be prepared. |
 | A bike friendly letterbox is located in an area where bicycles or mountain bikes are permitted and have plenty of room to roam. For instance, while it is legal to ride ones bicycle on busy city streets, it is not considered bike friendly if there are no designated bike lanes available for use near the letterbox. And while many trails may be accessible to mountain bike, it is not considered bike friendly if the trail is for hikers only. |
 | An urban letterbox, as defined here, is located in an area where one is unlikely to experience “The Great Outdoors.” Like in a big city, such as New York city. A rest area in the middle of nowhere is an urban box. A large city park with trees and hiking trails is not an urban box. The 'setting' for the letterbox is urban, not necessarily the location, if that makes any sense. |
 | The trail or path to the letterbox should be accessible by wheelchairs or strollers the entire way. However, the letterbox itself may not be reachable from a wheelchair or stroller, and those using them may need assistance from others to actually acquire the box. The letterbox may be planted too high or low for someone in a wheelchair to physically reach, or too far off from the main trail for a wheelchair, but as long as an assistant can retrieve the box and bring it back for the wheelchair-bound person, it's considered wheelchair accessible. |
 | The finder will be expected to use their head on this one in order to decipher the clue. The code might be easy or hard—but it definitely won’t be straight-forward. |
 | This letterbox requires payment of some sort of fee-probably a parking or entrance fee. The lack of this picture does not necessarily mean no fees are required. The creator may not have specified fees, or perhaps fees were added since the box was planted. It's always a good idea to carry a few extra dollars in case of an unexpected fee or two. |
 | This letterbox is available only for a limited time. A limited time letterbox is either a box that is planted for only part of the year or a box that you intend to retire within the next three months. Letterboxes planted in regions that are covered in snow for nine months of the year or in stores that require a visit during store hours do not count as limited time boxes. |
 | A box that requires some sort of special or unusual equipment like for scuba diving or rock climbing, or even something as simple as a ladder. A compass is not considered “special” equipment for letterboxers! |
 | Those who plant letterboxes are able to point out their favorite plants by assigning them the Planter’s Choice Award. They might do this because they consider it one of their best boxes, or perhaps it has sentimental value. Whatever the reason, the planter wants you to notice this box. |
