Background and aims: In slow-transit constipation (STC) pancolonic manometry shows significantly reduced antegrade propagating sequences (PS) and no response to physiological stimuli. This study aimed to determine whether transcutaneous electrical stimulation using interferential current (IFC) applied to the abdomen increased colonic PS in STC children. Methods: Eight children (8-18 years) with confirmed STC had 24-h colonic manometry using a water-perfused, 8-channel catheter with 7.5 cm sidehole distance introduced via appendix stomas. They then received 12 sessions (20 min/3 × per week) of IFC stimulation (2 paraspinal and 2 abdominal electrodes), applied at a comfortable intensity (< 40 mA, carrier frequency 4 kHz, varying beat frequency 80-150 Hz). Colonic manometry was repeated 2 (n = 6) and 7 (n = 2) months after IFC. Results: IFC significantly increased frequency of total PS/24 h (mean ± SEM, pre 78 ± 34 vs post 210 ± 62, p = 0.008, n = 7), antegrade PS/24 h (43 ± 16 vs 112 ± 20, p = 0.01) and high amplitude PS (HAPS/24 h, 5 ± 2:10 ± 3, p = 0.04), with amplitude, velocity, or propagating distance unchanged. There was increased activity on waking and 4/8 ceased using antegrade continence enemas. Conclusions and inferences: Transcutaneous IFC increased colonic PS frequency in STC children with effects lasting 2-7 months. IFC may provide a treatment for children with treatment-resistant STC.