Stach, 23, only has five caps at youth level, earning them as Germany won the UEFA European U21 Championship last summer. His senior nomination comes on the back of a breakout campaign with Mainz, making 21 Bundesliga appearances for the club since joining from Greuther Fürth at the start of the season.
A holding midfielder who came through the Werder Bremen youth system, Stach has helped the 05ers create a formidable defensive setup that has only conceded eight goals in 13 home games this season. That's four fewer than any other Bundesliga team. He has also contributed at the other end with a goal and three assists.
There is also a first call-up in five years for former Borussia Dortmund midfielder Julian Weigl.
The March games are Germany's first fixtures of the year, which culminates in the 2022 FIFA World Cup in Qatar.
Die Nationalmannschaft host Israel at Hoffenheim's PreZero Arena on Saturday, 26 March before heading to Amsterdam to take on arch-rivals the Netherlands on Tuesday, 29 March.
Full squad
Goalkeepers
Manuel Neuer (Bayern Munich), Marc-Andre ter Stegen (Barcelona), Kevin Trapp (Eintracht Frankfurt)
Defenders
Matthias Ginter (Borussia Mönchengladbach), Christian Günter (Freiburg), Benjamin Henrichs (RB Leipzig), Thilo Kehrer (Paris Saint-Germain), Robin Koch (Leeds United), David Raum (Hoffenheim), Antonio Rüdiger (Chelsea), Nico Schlotterbeck (Freiburg), Jonathan Tah (Bayer Leverkusen)
Midfielders
Ilkay Gündogan (Manchester City), Joshua Kimmich (Bayern Munich), Jamal Musiala (Bayern Munich), Florian Neuhaus (Borussia Mönchengladbach), Anton Stach (Mainz), Julian Weigl (Benfica)
Forwards
Karim Adeyemi (Red Bull Salzburg), Julian Draxler (Paris Saint-Germain), Serge Gnabry (Bayern Munich), Kai Havertz (Chelsea), Thomas Müller (Bayern Munich), Lukas Nmecha (Wolfsburg), Leroy Sane (Bayern Munich), Timo Werner (Chelsea)
*Bundesliga players in bold