|Nickname(es):||Matt, "Hot New Voice"|
|Affiliation:||US State Department|
|Significant other(s):||Daisy Grant (on-and-off girlfriend)|
|Played by:||Geoffrey Arend|
|Seasons:||1, 2, 3, 4|
Matthew "Matt" Mahoney is Elizabeth's speechwriter.
He worked under US Secretary of State Vincent Marsh until his unfortunate death and continued his tenure as a speechwriter under Elizabeth McCord. He was forced to spy on Marsh by Russell Jackson. When Elizabeth became the Secretary of State, Jackson wanted Mahoney to spy on Elizabeth as well. In return, Jackson will give Mahoney a job at the White House Office.
Mahoney suspected that the information he gave Jackson might have been the cause of Marsh's death. Due to this reason, Mahoney initially refused to spy on Elizabeth. He came clean to Elizabeth about the fact that Jackson wanted Mahoney to spy on her. Elizabeth told Mahoney to take the offer and become a double-agent for her to which he ultimately agreed. At first he only told Jackson the official information about Elizabeth with nothing out of the ordinary. At one point, Elizabeth wanted to test out her suspicion on Jackson so she told Mahoney to relay an information to Jackson telling him that Elizabeth had a conversation with Israeli Ambassador Lior Dori and he overheard something about Dubai.