diff --git a/config/config.go b/config/config.go
index afa0866cb..4adbc8b75 100644
--- a/config/config.go
+++ b/config/config.go
@@ -1025,6 +1025,7 @@ func parseConfig(contents []byte) (*ast.Table, error) {
 	contents = trimBOM(contents)
 
 	parameters := envVarRe.FindAllSubmatch(contents, -1)
+	var missingEnvVars []string
 	for _, parameter := range parameters {
 		if len(parameter) != 3 {
 			continue
@@ -1043,9 +1044,21 @@ func parseConfig(contents []byte) (*ast.Table, error) {
 		if ok {
 			envVal = escapeEnv(envVal)
 			contents = bytes.Replace(contents, parameter[0], []byte(envVal), 1)
+		} else {
+			missingEnvVars = append(missingEnvVars, string(envVar))
 		}
 	}
 
+	// Report all missing environment variables to the user
+	if len(missingEnvVars) > 0 {
+		errorMsg := "environment variable(s) not set:"
+		for _, e := range missingEnvVars {
+			errorMsg += e + " "
+		}
+
+		return nil, fmt.Errorf(errorMsg)
+	}
+
 	return toml.Parse(contents)
 }
 
diff --git a/config/config_test.go b/config/config_test.go
index 5a64cabca..0face446d 100644
--- a/config/config_test.go
+++ b/config/config_test.go
@@ -264,13 +264,15 @@ func TestConfig_WrongFieldType(t *testing.T) {
 func TestConfig_InlineTables(t *testing.T) {
 	// #4098
 	c := NewConfig()
+	require.NoError(t, os.Setenv("TOKEN", "test"))
 	require.NoError(t, c.LoadConfig("./testdata/inline_table.toml"))
 	require.Len(t, c.Outputs, 2)
 
 	output, ok := c.Outputs[1].Output.(*MockupOuputPlugin)
 	require.True(t, ok)
-	require.Equal(t, map[string]string{"Authorization": "Token $TOKEN", "Content-Type": "application/json"}, output.Headers)
+	require.Equal(t, map[string]string{"Authorization": "Token test", "Content-Type": "application/json"}, output.Headers)
 	require.Equal(t, []string{"org_id"}, c.Outputs[0].Config.Filter.TagInclude)
+	require.NoError(t, os.Unsetenv("TOKEN"))
 }
 
 func TestConfig_SliceComment(t *testing.T) {