diff --git a/CHANGELOG.md b/CHANGELOG.md
index e0506f31..47fdc3dd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/).
 
 -   fix new ktlint errors that come from our new default version of ktlint [#651](https://github.com/JLLeitschuh/ktlint-gradle/pull/651)
 -   fix syntax bug in release logic for VERSION_LATEST_RELEASE.txt [#651](https://github.com/JLLeitschuh/ktlint-gradle/pull/651)
+-   fix isRootEditorConfig [#664](https://github.com/JLLeitschuh/ktlint-gradle/pull/664)
 
 ### Changed
 
diff --git a/plugin/src/main/kotlin/org/jlleitschuh/gradle/ktlint/PluginUtil.kt b/plugin/src/main/kotlin/org/jlleitschuh/gradle/ktlint/PluginUtil.kt
index 7017db5f..6a7b19c8 100644
--- a/plugin/src/main/kotlin/org/jlleitschuh/gradle/ktlint/PluginUtil.kt
+++ b/plugin/src/main/kotlin/org/jlleitschuh/gradle/ktlint/PluginUtil.kt
@@ -70,9 +70,9 @@ private tailrec fun searchEditorConfigFiles(
     }
 }
 
-private val editorConfigRootRegex = "^root\\s?=\\s?true\\R".toRegex()
+private val editorConfigRootRegex = "^root\\s?=\\s?true".toRegex()
 
-private fun Path.isRootEditorConfig(): Boolean {
+internal fun Path.isRootEditorConfig(): Boolean {
     if (!Files.exists(this) || !Files.isReadable(this)) return false
 
     toFile().useLines { lines ->
diff --git a/plugin/src/test/kotlin/org/jlleitschuh/gradle/ktlint/PluginUtilTest.kt b/plugin/src/test/kotlin/org/jlleitschuh/gradle/ktlint/PluginUtilTest.kt
new file mode 100644
index 00000000..43ef281b
--- /dev/null
+++ b/plugin/src/test/kotlin/org/jlleitschuh/gradle/ktlint/PluginUtilTest.kt
@@ -0,0 +1,43 @@
+package org.jlleitschuh.gradle.ktlint
+
+import org.junit.jupiter.api.Assertions
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.io.TempDir
+import java.io.File
+
+internal class PluginUtilTest {
+    @TempDir
+    lateinit var temporaryFolder: File
+
+    @Test
+    fun `test isRootEditorConfig returns true`() {
+        temporaryFolder.resolve("test-pos.txt").apply {
+            createNewFile()
+            writeText(
+                """
+                root=true
+                """.trimIndent()
+            )
+            Assertions.assertTrue(this.toPath().isRootEditorConfig()) {
+                "correctly detects root"
+            }
+            delete()
+        }
+    }
+
+    @Test
+    fun `test isRootEditorConfig returns false`() {
+        temporaryFolder.resolve("test-neg.txt").apply {
+            createNewFile()
+            writeText(
+                """
+                [*.kt]
+                """.trimIndent()
+            )
+            Assertions.assertFalse(this.toPath().isRootEditorConfig()) {
+                "correctly does not match non-root file"
+            }
+            delete()
+        }
+    }
+}