Any cost or other expense involved in a transaction but not directly related to it. For example, one may see a concert ticket advertised for $13 (no sales tax) but actually spend $30 on the ticket because of convenience and processing fees. Those fees are collectively called ancillary charges.

What does it mean if something is ancillary?

ancillary \AN-suh-lair-ee\ adjective. 1 : of lower or secondary class or rank : subordinate, subsidiary. 2 : providing additional help or support : auxiliary, supplementary.

What does ancillary work mean?

adjective [ADJ n] The ancillary workers in an institution are the people such as cleaners and cooks whose work supports the main work of the institution.