diff --git a/src/nix-env/nix-env.cc b/src/nix-env/nix-env.cc
index 5e3de20c5..b42fa06bc 100644
--- a/src/nix-env/nix-env.cc
+++ b/src/nix-env/nix-env.cc
@@ -16,6 +16,7 @@
 #include "xml-writer.hh"
 #include "legacy.hh"
 #include "eval-settings.hh" // for defexpr
+#include "terminal.hh"
 
 #include <cerrno>
 #include <ctime>
@@ -1089,7 +1090,7 @@ static void opQuery(Globals & globals, Strings opFlags, Strings opArgs)
         return;
     }
 
-    bool tty = isatty(STDOUT_FILENO);
+    bool tty = shouldANSI();
     RunPager pager;
 
     Table table;
diff --git a/src/nix/main.cc b/src/nix/main.cc
index 5af5f2e41..c88b35005 100644
--- a/src/nix/main.cc
+++ b/src/nix/main.cc
@@ -16,6 +16,7 @@
 #include "loggers.hh"
 #include "markdown.hh"
 #include "memory-input-accessor.hh"
+#include "terminal.hh"
 
 #include <sys/types.h>
 #include <sys/socket.h>
@@ -375,7 +376,9 @@ void mainWrapped(int argc, char * * argv)
 
     setLogFormat("bar");
     settings.verboseBuild = false;
-    if (isatty(STDERR_FILENO)) {
+
+    // If on a terminal, progress will be displayed via progress bars etc. (thus verbosity=notice)
+    if (nix::shouldANSI()) {
         verbosity = lvlNotice;
     } else {
         verbosity = lvlInfo;
diff --git a/src/nix/prefetch.cc b/src/nix/prefetch.cc
index fabec5d88..f96381408 100644
--- a/src/nix/prefetch.cc
+++ b/src/nix/prefetch.cc
@@ -11,6 +11,7 @@
 #include "legacy.hh"
 #include "posix-source-accessor.hh"
 #include "misc-store-flags.hh"
+#include "terminal.hh"
 
 #include <nlohmann/json.hpp>
 
@@ -188,7 +189,7 @@ static int main_nix_prefetch_url(int argc, char * * argv)
 
         Finally f([]() { stopProgressBar(); });
 
-        if (isatty(STDERR_FILENO))
+        if (shouldANSI())
           startProgressBar();
 
         auto store = openStore();