diff --git a/internal/mire/diff_test.go b/internal/mire/diff_test.go
index b8334ab..f30c6ef 100644
--- a/internal/mire/diff_test.go
+++ b/internal/mire/diff_test.go
@@ -4,6 +4,8 @@ import (
 	"bytes"
 	"strings"
 	"testing"
+
+	"mire/internal/testutil"
 )
 
 func TestFirstMismatchingLineReturnsFirstChangedLine(t *testing.T) {
@@ -110,8 +112,6 @@ func TestCompareOutputDoesNotIgnoreMissingLine(t *testing.T) {
 }
 
 func TestWriteScenarioMismatchPrintsOnlyFirstMismatch(t *testing.T) {
-	t.Setenv("NO_COLOR", "1")
-
 	var buf bytes.Buffer
 	writeScenarioMismatch(&buf, &testMismatchError{
 		expected: []byte("$ echo x\nx\n$ \nexit\n"),
@@ -123,7 +123,7 @@ func TestWriteScenarioMismatchPrintsOnlyFirstMismatch(t *testing.T) {
 		},
 	})
 
-	got := buf.String()
+	got := testutil.StripANSI(buf.String())
 	for _, want := range []string{
 		"Expected\n",
 		"$ echo x\n",
@@ -146,8 +146,6 @@ func TestWriteScenarioMismatchPrintsOnlyFirstMismatch(t *testing.T) {
 }
 
 func TestWriteScenarioMismatchFormatsMissingLine(t *testing.T) {
-	t.Setenv("NO_COLOR", "1")
-
 	var buf bytes.Buffer
 	writeScenarioMismatch(&buf, &testMismatchError{
 		expected: []byte("alpha\nbeta\n"),
@@ -159,7 +157,7 @@ func TestWriteScenarioMismatchFormatsMissingLine(t *testing.T) {
 		},
 	})
 
-	got := buf.String()
+	got := testutil.StripANSI(buf.String())
 	if !strings.Contains(got, "beta\n") {
 		t.Fatalf("writeScenarioMismatch() output = %q, want expected mismatching line", got)
 	}
@@ -169,8 +167,6 @@ func TestWriteScenarioMismatchFormatsMissingLine(t *testing.T) {
 }
 
 func TestWriteScenarioMismatchItalicizesLabels(t *testing.T) {
-	t.Setenv("NO_COLOR", "")
-
 	var buf bytes.Buffer
 	writeScenarioMismatch(&buf, &testMismatchError{
 		expected: []byte("alpha\n"),
diff --git a/internal/mire/rewrite_test.go b/internal/mire/rewrite_test.go
index 4e59a45..d1320b0 100644
--- a/internal/mire/rewrite_test.go
+++ b/internal/mire/rewrite_test.go
@@ -70,13 +70,14 @@ func TestRewriteContinuesAfterFailureAndReturnsError(t *testing.T) {
 	if !strings.Contains(err.Error(), "1 scenario(s) failed to rewrite") {
 		t.Fatalf("rewrite() error = %q, want failed rewrite summary", err.Error())
 	}
+	normalizedStdout := testutil.StripANSI(stdout.String())
 	for _, want := range []string{
 		"FAIL bad (",
 		"PASS ok (",
 		"Summary: total=2 passed=1 failed=1",
 	} {
-		if !strings.Contains(stdout.String(), want) {
-			t.Fatalf("stdout = %q, want substring %q", stdout.String(), want)
+		if !strings.Contains(normalizedStdout, want) {
+			t.Fatalf("stdout = %q, want substring %q", normalizedStdout, want)
 		}
 	}
 	if got := testutil.ReadFile(t, filepath.Join(testDir, "bad", "out")); got != "stale bad\n" {
diff --git a/internal/output/output.go b/internal/output/output.go
index 7962355..ea2f2d0 100644
--- a/internal/output/output.go
+++ b/internal/output/output.go
@@ -52,10 +52,6 @@ func Label(text string, color Color) string {
 	return label(text, color)
 }
 
-func noColor() bool {
-	return os.Getenv("NO_COLOR") != ""
-}
-
 func prefix() string {
 	chevron := NewStyle().FG(palette.chevronTeal).Bold().Italic().Apply("›")
 	return NewStyle().FG(palette.mireGreen).Bold().Italic().Apply("mire") + " " + chevron + " "
diff --git a/internal/output/output_test.go b/internal/output/output_test.go
index 5420f0f..000572c 100644
--- a/internal/output/output_test.go
+++ b/internal/output/output_test.go
@@ -1,14 +1,11 @@
 package output
 
 import (
-	"os"
 	"strings"
 	"testing"
 )
 
-func TestFormatIncludesANSIByDefault(t *testing.T) {
-	t.Setenv("NO_COLOR", "")
-
+func TestFormatIncludesANSI(t *testing.T) {
 	got := Format("hello\n")
 	if !strings.Contains(got, "\x1b[") {
 		t.Fatalf("Format() = %q, want ANSI styling", got)
@@ -18,41 +15,24 @@ func TestFormatIncludesANSIByDefault(t *testing.T) {
 	}
 }
 
-func TestFormatPlainWhenNoColorSet(t *testing.T) {
-	t.Setenv("NO_COLOR", "1")
-
-	if got := Format("hello\n"); got != "mire › hello\n" {
-		t.Fatalf("Format() = %q, want %q", got, "mire › hello\n")
-	}
-}
-
-func TestLabelsPlainWhenNoColorSet(t *testing.T) {
-	t.Setenv("NO_COLOR", "1")
-
-	if got := Label("RUN", Info); got != "RUN" {
-		t.Fatalf("Label() = %q, want %q", got, "RUN")
-	}
-	if got := Label("PASS", Pass); got != "PASS" {
-		t.Fatalf("Label() = %q, want %q", got, "PASS")
-	}
-	if got := Label("FAIL", Fail); got != "FAIL" {
-		t.Fatalf("Label() = %q, want %q", got, "FAIL")
-	}
-}
-
-func TestFormatReadsNoColorAtRuntime(t *testing.T) {
-	t.Setenv("NO_COLOR", "")
-
-	styled := Format("hello\n")
-	if err := os.Setenv("NO_COLOR", "1"); err != nil {
-		t.Fatalf("Setenv() error = %v", err)
-	}
-
-	plain := Format("hello\n")
-	if !strings.Contains(styled, "\x1b[") {
-		t.Fatalf("styled Format() = %q, want ANSI styling", styled)
-	}
-	if plain != "mire › hello\n" {
-		t.Fatalf("plain Format() = %q, want %q", plain, "mire › hello\n")
+func TestLabelIncludesANSI(t *testing.T) {
+	for _, tc := range []struct {
+		name  string
+		text  string
+		color Color
+	}{
+		{name: "info", text: "RUN", color: Info},
+		{name: "pass", text: "PASS", color: Pass},
+		{name: "fail", text: "FAIL", color: Fail},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			got := Label(tc.text, tc.color)
+			if !strings.Contains(got, "\x1b[") {
+				t.Fatalf("Label() = %q, want ANSI styling", got)
+			}
+			if !strings.Contains(got, tc.text) {
+				t.Fatalf("Label() = %q, want text %q", got, tc.text)
+			}
+		})
 	}
 }
diff --git a/internal/output/termstyle.go b/internal/output/termstyle.go
index 5822780..4538fe2 100644
--- a/internal/output/termstyle.go
+++ b/internal/output/termstyle.go
@@ -40,7 +40,7 @@ func (s Style) BG(rgb uint32) Style {
 }
 
 func (s Style) Apply(text string) string {
-	if noColor() || (!s.bold && !s.italic && s.fg == nil && s.bg == nil) {
+	if !s.bold && !s.italic && s.fg == nil && s.bg == nil {
 		return text
 	}
 
diff --git a/internal/testutil/testutil.go b/internal/testutil/testutil.go
index c1ada4d..44f36b4 100644
--- a/internal/testutil/testutil.go
+++ b/internal/testutil/testutil.go
@@ -6,14 +6,16 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"regexp"
 	"strings"
 	"sync"
 	"testing"
 )
 
+var ansiRegexp = regexp.MustCompile(`\x1b\[[0-9;]*[A-Za-z]`)
+
 func CaptureOutput(t *testing.T, fn func()) (string, string) {
 	t.Helper()
-	t.Setenv("NO_COLOR", "1")
 
 	stdoutReader, stdoutWriter, err := os.Pipe()
 	if err != nil {
@@ -52,12 +54,11 @@ func CaptureOutput(t *testing.T, fn func()) (string, string) {
 		t.Fatalf("stderr copy error = %v", err)
 	}
 
-	return stdoutBuf.String(), stderrBuf.String()
+	return StripANSI(stdoutBuf.String()), StripANSI(stderrBuf.String())
 }
 
 func CapturePromptedOutput(t *testing.T, sessionInput, promptMarker, promptInput string, fn func()) (string, string) {
 	t.Helper()
-	t.Setenv("NO_COLOR", "1")
 
 	stdinReader, stdinWriter, err := os.Pipe()
 	if err != nil {
@@ -159,7 +160,11 @@ func CapturePromptedOutput(t *testing.T, sessionInput, promptMarker, promptInput
 		t.Fatalf("stderr copy error = %v", err)
 	}
 
-	return stdoutBuf.String(), stderrBuf.String()
+	return StripANSI(stdoutBuf.String()), StripANSI(stderrBuf.String())
+}
+
+func StripANSI(text string) string {
+	return ansiRegexp.ReplaceAllString(text, "")
 }
 
 func WriteFile(t *testing.T, path, content string) {