diff --git a/memory-bank/change-log.md b/memory-bank/change-log.md
index f0fad0e1..d1274006 100644
--- a/memory-bank/change-log.md
+++ b/memory-bank/change-log.md
@@ -689,3 +689,39 @@ Validation:
 Follow-ups:
 
 - Optional further hygiene pass can target remaining oversized commented historical sections in non-sensitive handlers.
+
+---
+
+### CL-018: TASK22224 nextauth notify micro-refactor
+
+date: 2026-03-24
+author: Cline
+scope: `pages/api/auth/[...nextauth].js`
+type: change
+rationale: Execute the explicitly approved auth micro-slice by replacing inline promise `.catch(...)` with explicit `try/catch` while preserving existing auth behavior.
+impact: Auth-sensitive non-functional refactor only; keeps current sign-in flow, template/locale routing, and error-handling semantics unchanged.
+status: completed
+
+Summary:
+
+- `pages/api/auth/[...nextauth].js`
+    - replaced:
+        - `await notifyClient.sendEmail(...).catch((error) => consoleLogger(error))`
+    - with explicit:
+        - `try { await notifyClient.sendEmail(...) } catch (error) { consoleLogger(error) }`
+- preserved behavior contracts:
+    - Notify failures are still logged and do not throw through auth handler
+    - no changes to callback URL construction, locale/template selection, NextAuth options, session/cookies/pages config
+
+Validation:
+
+- `node tests/phase21/api-contract-slice1.test.cjs` -> pass
+    - helper: 4/4
+    - file-handler: 53/53
+    - email-handler: 12/12
+    - endpoint-handler: 152/152
+    - documents-handler: 3/3
+
+Follow-ups:
+
+- Optional future auth hygiene (separate guarded slice): replace verbose auth `console.log` diagnostics with structured logger usage once production logging requirements are confirmed.
diff --git a/pages/api/auth/[...nextauth].js b/pages/api/auth/[...nextauth].js
index 75939546..7a713e47 100644
--- a/pages/api/auth/[...nextauth].js
+++ b/pages/api/auth/[...nextauth].js
@@ -139,8 +139,8 @@ const authOptions = (req, res) => {
                         process.env.NOTIFY_API_KEY
                     );
 
-                    await notifyClient
-                        .sendEmail(
+                    try {
+                        await notifyClient.sendEmail(
                             effectiveLocale === "cy"
                                 ? templateIdcy
                                 : templateId,
@@ -149,8 +149,10 @@ const authOptions = (req, res) => {
                                 personalisation,
                                 reference
                             }
-                        )
-                        .catch((error) => consoleLogger(error));
+                        );
+                    } catch (error) {
+                        consoleLogger(error);
+                    }
                 }
             })
         ],