Methods and systems are disclosed for inferring address and subnet relationships. An exemplary method includes identifying a first address associated with a subnet; determining a length of a prefix part of the first address; determining a length of a prefix part of a second address; determining when a portion of the second address matches a portion of the first address; and determining when the lengths of the prefix parts of the first and second addresses are equal. A relationship between the second address and the subnet is inferred when the portion of the second address matches the portion of the first address and the lengths of the prefix parts of the first and second addresses are equal.