Rupture of the renal collecting system is a rare event, usually occurring at the ureterovesical junction (UVJ). The most common cause is nephrolithiasis, usually directly correlated with the size of the stone. Other causes include bladder outlet obstruction, ureteropelvic junction obstruction, and extrinsic ureteral compression by a malignant pathology. The mechanism is increased pressure within the collecting system, and symptoms vary from vague mild abdominal pain to severe excruciating pain. We present a case of a 19-year-old female with obstructive uropathy and renal calyceal rupture caused by a 3 mm stone at the UVJ. Due to the small size of the stone and her hemodynamic stability, she was treated conservatively with tamsulosin and IV ceftriaxone. The following day she passed sediment in the urine and noted pain improvement. Calyceal rupture with small stones is exceedingly rare, may be missed on a CT without contrast, and should be suspected when perinephric edema or fluid is seen. This is the smallest recorded stone causing calyceal rupture to the best of our knowledge. CT with contrast is indicated for diagnosis when calyceal rupture is suspected and is suggested by extravasation of contrast. Early diagnosis and intervention, in collaboration with urologists, can help to avoid long-term complications such as acute kidney injury, urosepsis, and urinoma. Conservative management may still be considered after a calyceal rupture in patients with small, potentially passable stones. However, if there is associated obstructive uropathy, infection, or significant rupture, then stenting may be indicated. This case highlights the diagnosis of calyceal rupture in the setting of tiny stones and the efficacy of conservative therapy versus early stenting in the management of stable patients.