01821 is zip code located in Billerica, Massachusetts. The population is 30,569, making 01821 the largest zipcode in Billerica.
There are 8 public schools in 01821 with an average Homefacts rating of B. The total crime rate for Billerica is very low , and there are 6 registered sex offenders residing in the zip code 01821. Unemployment in 01821 is moderate.