Over at WordReference, there is a topic on how to get across the idea in Portuguese of saying someone lives on the outskirts of the city. There are a few options for you and a tiny bit of caution needs to be taken when deciding which to use. Just add “da cidade” to the end of one of the phrases below to say “on the outskirts of the city”.
Best to Use
nos arredores (in the surroundings), nas cercanias (same as arredores).
Best to Avoid
nos subúrbios (in the suburbs), na periferia (on the periphery).