I currently live on the edge of Hellertown and Bethlehem. While are address is considered Bethlehem, our zip is 18015. If you are familiar with the area- I believe once you pass Saucon Park (coming from Bethlehem) you only have a block or so left of Bethlehem, considering the Turkey Hill on Hellertown Road is considered Hellertown. Basically if you take Main street hellertown down toward bethlehem, it turns into Hellertown Road. Hellertown road lies partially in Hellertown, and partially in Bethlehem.

Searching by zip code is never a smart way to look for a home. Search by municipality or school district.

18015 and 18017 are in Lower Saucon Township and 18055 is in Hellertown. Hellertown and Lower Saucon combine to make up Saucon Valley School District. So, yes, it would make sense for you to look in all of these areas for your home!

This question bring up a good point: make sure that you are including all the areas that will work for you. An experienced Realtor will know the area and may be able to suggest some zip codes that you missed.
Happy Hunting,
Mim

Bethlehem 18017 is right up rte 412, across the Lehigh river. It is in the city of Bethlehem.
18015 is just to the west of hellertown, across rte 412.