Various embodiments of a cartridge are disclosed, for loading a suture onto a suturing instrument and, in some embodiments, for loading a pre-tied knot formed from the suture onto the suturing instrument. The suturing instrument is typically of the type having a suture passing member defining a suture receiving passage therein. The cartridge may be operable to load the suture and/or the knot onto the suturing instrument at a point of use. In some embodiments, the cartridge defines a path for insertion thereto and withdrawal therefrom of the suturing instrument. The cartridge further comprises a seat for releasably holding a portion of a suture and a mechanism for transferring the suture from seat to the suturing instrument, various features of which are described herein.