diff --git a/compose-lint-checks/src/main/java/slack/lint/compose/M2ApiDetector.kt b/compose-lint-checks/src/main/java/slack/lint/compose/M2ApiDetector.kt
index 326b4747..bba637ba 100644
--- a/compose-lint-checks/src/main/java/slack/lint/compose/M2ApiDetector.kt
+++ b/compose-lint-checks/src/main/java/slack/lint/compose/M2ApiDetector.kt
@@ -6,7 +6,7 @@ import com.android.tools.lint.client.api.UElementHandler
 import com.android.tools.lint.detector.api.Category.Companion.CORRECTNESS
 import com.android.tools.lint.detector.api.Issue
 import com.android.tools.lint.detector.api.JavaContext
-import com.android.tools.lint.detector.api.Severity.IGNORE
+import com.android.tools.lint.detector.api.Severity.ERROR
 import com.android.tools.lint.detector.api.SourceCodeScanner
 import com.android.tools.lint.detector.api.StringOption
 import com.android.tools.lint.detector.api.TextFormat
@@ -47,10 +47,11 @@ constructor(private val allowList: StringSetLintOption = StringSetLintOption(ALL
             """,
           category = CORRECTNESS,
           priority = NORMAL,
-          severity = IGNORE,
+          severity = ERROR,
           implementation = sourceImplementation<M2ApiDetector>()
         )
         .setOptions(listOf(ALLOW_LIST))
+        .setEnabledByDefault(false)
   }
 
   override fun getApplicableUastTypes() =
diff --git a/compose-lint-checks/src/test/java/slack/lint/compose/M2ApiDetectorTest.kt b/compose-lint-checks/src/test/java/slack/lint/compose/M2ApiDetectorTest.kt
index abe19c74..4db19653 100644
--- a/compose-lint-checks/src/test/java/slack/lint/compose/M2ApiDetectorTest.kt
+++ b/compose-lint-checks/src/test/java/slack/lint/compose/M2ApiDetectorTest.kt
@@ -97,23 +97,23 @@ class M2ApiDetectorTest : BaseSlackLintTest() {
       .run()
       .expect(
         """
-          src/test.kt:9: Warning: Compose Material 2 (M2) is succeeded by Material 3 (M3). Please use M3 APIs.
+          src/test.kt:9: Error: Compose Material 2 (M2) is succeeded by Material 3 (M3). Please use M3 APIs.
           See https://slackhq.github.io/compose-lints/rules/#use-material-3 for more information. [ComposeM2Api]
             Text("Hello, world!")
             ~~~~~~~~~~~~~~~~~~~~~
-          src/test.kt:23: Warning: Compose Material 2 (M2) is succeeded by Material 3 (M3). Please use M3 APIs.
+          src/test.kt:23: Error: Compose Material 2 (M2) is succeeded by Material 3 (M3). Please use M3 APIs.
           See https://slackhq.github.io/compose-lints/rules/#use-material-3 for more information. [ComposeM2Api]
               Text("Hello, world!")
               ~~~~~~~~~~~~~~~~~~~~~
-          src/test.kt:24: Warning: Compose Material 2 (M2) is succeeded by Material 3 (M3). Please use M3 APIs.
+          src/test.kt:24: Error: Compose Material 2 (M2) is succeeded by Material 3 (M3). Please use M3 APIs.
           See https://slackhq.github.io/compose-lints/rules/#use-material-3 for more information. [ComposeM2Api]
               val elevation = BottomNavigationDefaults.Elevation
                               ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-          src/test.kt:25: Warning: Compose Material 2 (M2) is succeeded by Material 3 (M3). Please use M3 APIs.
+          src/test.kt:25: Error: Compose Material 2 (M2) is succeeded by Material 3 (M3). Please use M3 APIs.
           See https://slackhq.github.io/compose-lints/rules/#use-material-3 for more information. [ComposeM2Api]
               val drawerValue = BottomDrawerValue.Closed
                                 ~~~~~~~~~~~~~~~~~~~~~~~~
-          0 errors, 4 warnings
+          4 errors, 0 warnings
         """
           .trimIndent()
       )
diff --git a/docs/rules.md b/docs/rules.md
index acf1cde5..f1ef99f0 100644
--- a/docs/rules.md
+++ b/docs/rules.md
@@ -302,20 +302,20 @@ Rule: [`ComposeM2Api`](https://github.com/slackhq/compose-lints/blob/main/compos
 Material 3 (M3) reached stable in October 2022. In apps that have migrated to M3, there may be `androidx.compose.material` (M2) APIs still remaining on the classpath from libraries or dependencies that can cause confusing imports due to the many similar or colliding Composable names in the two libraries. The `ComposeM2Api` rule can prevent these from being used.
 
 !!! warning "Lint Configuration"
-    This rule is set to `IGNORE` by default and is **opt-in**.
+    This rule is disabled default and is **opt-in**.
     
-    You can make it an error via the `lint` DSL in Gradle:
+    You can enable it via the `lint` DSL in Gradle:
     ```kotlin
     android {
       lint {
-        error += "ComposeM2Api"
+        enable += "ComposeM2Api"
       }
     }
     ```
     Or in `lint.xml`:
     ```xml
     <lint>
-      <issue id="ComposeM2Api" severity="error" />
+      <issue id="ComposeM2Api" severity="error"/>
     </lint>
     ```
     More lint configuration docs can be found [here](https://developer.android.com/studio/write/lint#gradle).
@@ -323,7 +323,7 @@ Material 3 (M3) reached stable in October 2022. In apps that have migrated to M3
 !!! note "Allow-list Configuration"
     To allow certain APIs (i.e. for incremental migration), you can configure a `allowed-m2-apis` option in `lint.xml`.
     ```xml
-    <issue id="ComposeM2Api">
+    <issue id="ComposeM2Api"  severity="error">
        <option name="allowed-m2-apis" value="Text,Surface" />
     </issue>
     ```