Loose or detached sofa buttons are a nuisance, and can turn into an eyesore if left in a state of disrepair. The two easiest ways to attach loose sofa buttons are with hot fabric glue or by resewing the button to the sofa cushion. Attaching a button with fabric glue is a temporary repair, and can be done quickly if you're expecting company or don't have time to sew the button to the sofa. For a longer-lasting repair, sew the button onto the sofa cushion.
Pick any loose threads from beneath the button or from the button location on the sofa. Use your fingernails to scrape the fabric where the button attaches to fluff the fibres for a better bond between the fabric glue and the button back.
Squirt a pea-sized dot of hot fabric glue onto the back of the button around the shank.
Press the shank and button back onto the button location on the sofa cushion. Allow the glue to dry before using the sofa. The repair will last longer the less the sofa is used. When the button no longer adheres to the fabric, use your fingers or tweezers to remove the glue pieces from the back of the button before regluing or sewing the button to the sofa.
Thread a straight or curved upholstery needle with 16 inches of button thread that matches the most dominant colour in the sofa fabric. Pull the thread through the needle. Align the ends and tie a knot (the thread is now a double strand measuring 8 inches long).
Insert the needle above the needle holes where the button originally was attached. If you can't see the original holes, insert the needle into the centre of the spot where the button should be located. Pull the thread until the knot meets the fabric. Insert the needle back into the sofa fabric and back out, forming a stitch to lock the thread.
Feed the needle and thread through the sofa button's shank.
Insert the needle into the sofa over the previously sewn locking stitch and back out again. Pull the thread until the button's shank touches the sofa fabric. Continue feeding the needle and thread through the shank, and then through the sofa fabric until you have about 2 inches of thread left. Sew a stitch beside the button shank, through the fabric only, to lock the thread. Cut the thread.
Squirt a very small dot of clear-drying super-strength or fabric glue over the thread on the shank.
Sofa buttons are typically shank buttons, which have a metal or plastic loop or a fabric tuft through which thread is sewn to attach the button to the sofa upholstery or fabric. Some buttons may be attached at the factory by a metal staple or adhered with glue. Buttons that are not shank buttons can be sewn to a sofa, but it is difficult and time-consuming. Use tweezers to grasp a button shank if you're having difficulty holding onto it as you sew.