In this cohort, dwell times of 1FR-PICC lines removed non-electively were similar to 1.9- or 2.0FR-PICC. PICC tips positioned in the axillary, cephalic, external iliac, and femoral veins had a higher risk of non-elective removal. What is Known: •Peripherally inserted central catheters (PICC) are widely used in neonatal intensive care. •Previous studies focused on 2-French PICC and newborns of all gestational ages. What is New: •Dwell times of 1-French PICC removed non-electively were similar to 2-French PICC. •1-French PICC tips positioned more peripherally had a higher risk of non-elective removal.