This guide allows you to find all the mailboxes in the game. Getting the first 10 mailboxes will unlock the overdue packages sidequest. While getting them all will award you a wickerling.

The mailboxes are numbered in the image so it's easier to find them in the video.


The video on youtube has the timestamps for the mailboxes as numbered in the image.


Timestamps:

1 - 0:00 | 2 - 1:29 | 3 - 2:40
4 - 3:48 | 5 - 3:17 | 6 - 4:40
7 - 6:35 | 8 - 8:20 | 9 - 9:14
10 - 10:05 | 11- 11:06 | 12 - 11:34
13 - 12:29 | 14 - 13:37 | 15 - 14:19
16 - 14:37 | 17 - 15:10 | 18 - 15:47
19 - 16:10 | 20 - 17:38 | 21 - 17:49
22 - 18:13 | 23 - 18:35 | 24 - 18:54
25 - 20:04 | 26 - 20:18 | 27 - 20:36
28 - 21:53 | 29 - 24:29 | 30 - 24:58

Once you have delivered mail to 10 mailboxes you unlock the overdue packages side quest. In the video below you will find how to deliver each of the packages. You have to deliver a package to Treek, Sin and Quinbe.

Treek - 0:11 - This is a rather straight-forward delivery. Treek has moved and so you have to go through 3 houses looking for him.

Sin - 5:31 - Sin doesn't like being disturbed so knocking on his front door won't be enough to deliver the package. You have to go around and place it through the attic.

Quinbe - 7:37 - This is the tougher one. In order to get close to Quinbe you need a 'beesuit', this can be achieve by mixing the Creepy and Sweet Sprinkles.