Mundt signed with the Los Angeles Rams as an undrafted free agent on April 29, 2017.

[2] Mundt had a solid preseason competing with fellow rookie Travis Wilson for the team's possible third tight end spot behind Tyler Higbee and Gerald Everett.

[7] Mundt re-signed on a one-year exclusive-rights free agent contract with the Rams on April 17, 2020.

[10] Without Mundt, the Rams won Super Bowl LVI against the Cincinnati Bengals.

[11] On March 16, 2022, Mundt signed a two-year contract with the Minnesota Vikings.