To investigate the efficiency of triclosan, ethylenediaminetetraacetic acid (EDTA) and cranberry alone or in combinations against Escherichia coli strains as urinary catheter lock solutions to reduce catheter-associated urinary tract infections. Viable counting was used to assess antibiofilm activities for triclosan, EDTA and cranberry alone or in combinations against E. coli strains embedded in biofilm onto all-silicon Foley catheter surface. The results revealed that combination of triclosan (10 mg ml-1 /EDTA 30 mg ml-1 ) when filling the catheter balloon was able to eradicate and prevent biofilm formation among all tested E. coli including the resistant strains, whereas triclosan (8·5 mg ml-1 )/ cranberry (103 mg ml-1 ) combination was a successful catheter lock solution by preventing all tested strains from adhering onto catheter surface when filled via the eye hole. The combinations of triclosan/EDTA and triclosan/cranberry were significantly effective in eradicating and preventing biofilm formation of the tested E. coli strains on Foley catheters. Combinations of triclosan/EDTA and triclosan/cranberry have a promising application as nonantibiotic catheter lock solution. © 2019 The Society for Applied Microbiology.