Buy the overlocker first, in almost every case.
The reasoning is about what each machine solves. An overlocker addresses seams and raw edges — every seam in a knit garment, every seam allowance in a woven one. That is a problem on every project. A coverstitch addresses hems, which is one operation per garment and one for which a reasonable substitute exists.
The substitute matters. A twin needle on your sewing machine gives twin parallel rows with enough stretch for most jersey hems. There is no comparable substitute for what an overlocker does — a zigzag finishes an edge, but it does not trim and construct a stretchy seam in a single pass.
When the order reverses. If you already have an overlocker and hems are the thing that frustrates you, or you sew a lot of activewear and leggings where the coverstitch is doing constant work, a coverstitch is the sensible next purchase.
On combination machines. They do both and cost less than two machines, and they take one machine’s worth of space. The trade-off is conversion time: rethreading and reconfiguring between the two modes, which is enough of a chore that many owners batch their work into overlocking sessions and hemming sessions. That is workable, and it is worth knowing about before buying rather than after.
Space and thread. Two machines means two sets of cones, two covers and two patches of bench. Neither machine benefits from being packed away between sessions, because setting up is the part people avoid.
Questions people actually ask
Can I manage with neither?
Yes. A three-step zigzag finishes edges, a narrow zigzag sews knit seams, and a twin needle hems them. Slower and slightly less neat, entirely workable.
Are combination machines a compromise?
They are a real compromise on convenience rather than on stitch quality. If you convert often, the time adds up; if you batch your work, it barely matters.
Last reviewed 2026-08-11