diff --git a/.changeset/microsoft-token-claims.md b/.changeset/microsoft-token-claims.md
index 390fdde224..b5a351c098 100644
--- a/.changeset/microsoft-token-claims.md
+++ b/.changeset/microsoft-token-claims.md
@@ -2,4 +2,4 @@
 "@better-auth/core": minor
 ---
 
-Microsoft profile callbacks now accept numeric token timestamps, claim arrays, and omitted conditional claims or profile photos. Profile mappings must handle these corrected values instead of treating timestamps as `Date` objects or all claims as present.
+Microsoft profile callbacks now accept numeric token timestamps, claim arrays, boolean corporate-network flags, and omitted conditional or opaque claims and profile photos. Profile mappings must handle these corrected values instead of treating timestamps as `Date` objects or all claims as present.
diff --git a/packages/core/src/social-providers/microsoft-entra-id.test.ts b/packages/core/src/social-providers/microsoft-entra-id.test.ts
index 1158f9b7a7..53687486b3 100644
--- a/packages/core/src/social-providers/microsoft-entra-id.test.ts
+++ b/packages/core/src/social-providers/microsoft-entra-id.test.ts
@@ -345,6 +345,7 @@ describe("microsoft id_token alg omission", () => {
  * @see https://github.com/better-auth/better-auth/issues/3802
  * @see https://learn.microsoft.com/en-us/entra/identity-platform/id-token-claims-reference
  * @see https://learn.microsoft.com/en-us/entra/identity-platform/optional-claims-reference
+ * @see https://learn.microsoft.com/en-us/entra/identity-platform/access-token-claims-reference
  */
 it("accepts numeric Microsoft timestamps and configured claim arrays", async () => {
 	const profile = {
@@ -353,7 +354,6 @@ it("accepts numeric Microsoft timestamps and configured claim arrays", async ()
 		iat: 1700000000,
 		nbf: 1700000000,
 		exp: 1700003600,
-		aio: "opaque-value",
 		oid: "ms-stable-oid",
 		sub: "ms-pairwise-sub",
 		tid: WORK_TENANT_ID,
@@ -361,6 +361,8 @@ it("accepts numeric Microsoft timestamps and configured claim arrays", async ()
 	assertType<MicrosoftEntraIDProfile>(profile);
 	const configuredProfile = {
 		...profile,
+		aio: "opaque-value",
+		in_corp: true,
 		auth_time: 1700000000,
 		groups: ["group-id"],
 		acrs: ["c1"],
diff --git a/packages/core/src/social-providers/microsoft-entra-id.ts b/packages/core/src/social-providers/microsoft-entra-id.ts
index 5718a606bf..326783bd51 100644
--- a/packages/core/src/social-providers/microsoft-entra-id.ts
+++ b/packages/core/src/social-providers/microsoft-entra-id.ts
@@ -45,7 +45,7 @@ export interface MicrosoftEntraIDProfile extends Record<string, any> {
 	/** Access token hash included in ID tokens when issued with an OAuth 2.0 access token */
 	at_hash?: string;
 	/** Internal claim used to record data for token reuse */
-	aio: string;
+	aio?: string;
 	/** The primary username that represents the user */
 	preferred_username?: string;
 	/** User's email address */
@@ -121,7 +121,7 @@ export interface MicrosoftEntraIDProfile extends Record<string, any> {
 	/** Change Password URL */
 	pwd_url?: string;
 	/** Inside Corporate Network flag */
-	in_corp?: string;
+	in_corp?: boolean;
 	/** User's family name/surname */
 	family_name?: string;
 	/** User's given/first name */