January 29, 2018
Diamondbacks 
sign
Neftali Feliz
January 31, 2018
Diamondbacks
sign
Alex Avila
as a free agent
February 19, 2018
Diamondbacks
place
Shelby Miller
on the injured list
Diamondbacks
sign
Jarrod Dyson
as a free agent
February 20, 2018
Brandon Drury
traded from
Diamondbacks
to
Yankees
Anthony Banda
traded from
Diamondbacks
to
Rays
Taylor Widener
traded from
Yankees
to
Diamondbacks
Steven Souza
traded from
Rays
to
Diamondbacks
March 24, 2018
Deven Marrero
traded from
Red Sox
to
Diamondbacks
March 26, 2018
Diamondbacks
place
Steven Souza
on the injured list
April 02, 2018
Stefan Crichton
traded from
Orioles
to
Diamondbacks
April 03, 2018
Diamondbacks
place
Jake Lamb
on the injured list
April 15, 2018
Diamondbacks
place
Taijuan Walker
on the injured list
April 30, 2018
Diamondbacks
place
Robbie Ray
on the injured list
May 01, 2018
Colin Poche
traded from
Diamondbacks
to
Rays
May 15, 2018
Diamondbacks
place
AJ Pollock
on the injured list
Josh Taylor
traded from
Diamondbacks
to
Red Sox
May 22, 2018
Diamondbacks
place
Steven Souza
on the injured list
June 05, 2018
Diamondbacks
sign
Cristofer Ogando
June 06, 2018
Gabe Speier
traded from
Diamondbacks
to
Royals
Jon Jay
traded from
Royals
to
Diamondbacks
June 12, 2018
Diamondbacks
sign
Jake McCarthy
Diamondbacks
sign
Alek Thomas
June 22, 2018
Diamondbacks
sign
Tyler Holton
June 23, 2018
Diamondbacks
release
Stefan Crichton
June 27, 2018
Diamondbacks
place
Alex Avila
on the injured list
Diamondbacks
sign
Stefan Crichton
June 30, 2018
Diamondbacks
place
Deven Marrero
on the injured list
July 05, 2018
Diamondbacks
place
Jarrod Dyson
on the injured list
July 12, 2018
Diamondbacks
place
T.J. McFarland
on the injured list
Diamondbacks
place
Shelby Miller
on the injured list
July 25, 2018
Matt Andriese
traded from
Rays
to
Diamondbacks
Michael Perez
traded from
Diamondbacks
to
Rays
July 27, 2018
Diamondbacks
place
Jake Lamb
on the injured list
Eduardo Escobar
traded from
Twins
to
Diamondbacks
Jhoan Duran
traded from
Diamondbacks
to
Twins
July 31, 2018
Jake Diekman
traded from
Rangers
to
Diamondbacks
August 07, 2018
Diamondbacks
designate
Deven Marrero
for assignment
September 06, 2018
Patrick Kivlehan
traded from
Mets
to
Diamondbacks
September 29, 2018
Diamondbacks
place
Christian Walker
on the injured list
October 29, 2018
Patrick Corbin
became a free agent
Jon Jay
became a free agent
Jake Diekman
became a free agent
Jeff Mathis
became a free agent
AJ Pollock
became a free agent
November 06, 2018
Diamondbacks
sign
Abraham Almonte
November 12, 2018
Diamondbacks
sign
Tyler Heineman
Diamondbacks
sign
Wyatt Mathisen
November 26, 2018
Diamondbacks
sign
Rob Refsnyder
November 30, 2018
Chris Owings
became a free agent
Brad Boxberger
became a free agent
Shelby Miller
became a free agent
December 04, 2018
Diamondbacks
sign
Merrill Kelly
as a free agent
December 05, 2018
Paul Goldschmidt
traded from
Diamondbacks
to
Cardinals
Luke Weaver
traded from
Cardinals
to
Diamondbacks
Carson Kelly
traded from
Cardinals
to
Diamondbacks
Andy Young
traded from
Cardinals
to
Diamondbacks