NI Water is urging customers to be extra vigilant about bogus callers coming to their home and claiming to work for them.
The guidance comes as more people are at home, self-isolating and practising social distancing as a result of the coronavirus pandemic.
Carol Duffy, head of NI Water's customer service centre, said: "It is unusual that someone claiming to be from NI Water will need to call at your door in any circumstances.
"However, if someone does call, simply call the quick check number on 101. The quick check scheme provides reassurance to members of the public about callers to their door claiming to be from network companies.
"Anyone who wishes to check the identity of someone who says they are calling on the pretext of inspecting water, electricity or gas supplies can call the police non-emergency 101 number to verify their identity.
"Your call will be answered by a trained police call handler."