Gateshead Council has warned of a possible bogus council official targeting households in the Sheriff Hill area.
The council said it had received reports of a man wearing a high visibility jacket or tabard bearing the name "Gateshead Council" knocking on residents' doors.
He is reported to have asked residents for their views on blue recycling bins.
The council said no-one had been commissioned to carry out such work.
Anneliese Hutchinson, head of development and public protection, said: "We are advising residents to be extra cautious and if anyone visits them at home they should always, always ask for identification.
"Genuine Gateshead Council employees will always show their identification at your door, and you should always ask for this if it is not immediately offered."