ll.Jury System Jurors How long does jury service last for? It lasts for around two weeks,however, if at the end of this time the trial is still going,you may be asked if you are able to stay on.II. Jury System & Jurors How long does jury service last for? It lasts for around two weeks, however, if at the end of this time the trial is still going, you may be asked if you are able to stay on