An in-seam pocket is used in garment making to create a tailored, discrete pocket on pants, slacks, skirts, jackets and coats. A kind of internal pocket, it is placed inside the side seam of the garment and is entirely enclosed by the outer layers, leaving no visible flaps, buttons, zippers or snaps. In-seam pockets are primarily, though not exclusively, used on more fashionable garments so it does not detract from an overall formal look.
In-seam pockets tend to be dressier than external, hip or patch pockets, so they can be less useful, because they tend to have a narrow opening and limited storage capacity. Therefore, an in-seam pocket usually provides a relatively small space for stowing personal items and is not intended for larger or heavier items that might not fit inside. Another factor with these pockets is that because of their more fitted nature compared to other kinds of pockets, items placed inside are often visible in the form of a bulge from the outside, potentially detracting from an overall fitted, tailored look to the garment when it is worn.
It generally is agreed that in-seam pockets are not necessarily more difficult to make than other pocket types, but they do require some special planning if one is to set an in-seam pocket successfully. The two pieces of the pocket itself are first cut and sewn together before the seam of the garment is sewn. This is important because the pocket opening will be set flush with the seam of the garment. One then sews the seams, leaving the pocket opening unstitched. This will create a virtually undetectable pocket opening, which is the primary characteristic of this type of pocket.
It is possible to create an in-seam pocket and make it more visible, if desired. One merely cuts the pocket form slightly differently, leaving tabs that will be folded out over the edge of the garment seams. These tabs are known as welts and will be visible without being pronounced. This should not be confused with a welted pocket, which is similar but is not set into the garment seam. In addition to providing visual interest, welts also serve to strengthen the edges of pockets. Care should be taken when making an in-seam pocket with welts however, because it will be necessary to be precise in measuring and marking the position of the pockets and their welts.