diff --git a/src/libs/ReportUtils.ts b/src/libs/ReportUtils.ts
index 16413f1da16ae..0c5eb0869f499 100644
--- a/src/libs/ReportUtils.ts
+++ b/src/libs/ReportUtils.ts
@@ -7855,6 +7855,8 @@ type BuildOptimisticChatReportParams = {
     optimisticReportID?: string;
     isPinned?: boolean;
     chatReportID?: string;
+    // TODO: This'll be required eventually. Refactor issue: https://github.com/Expensify/App/issues/66412
+    currentUserAccountID?: number;
 };
 
 function buildOptimisticChatReport({
@@ -7875,12 +7877,13 @@ function buildOptimisticChatReport({
     optimisticReportID = '',
     isPinned = false,
     chatReportID = undefined,
+    currentUserAccountID = deprecatedCurrentUserAccountID,
 }: BuildOptimisticChatReportParams): OptimisticChatReport {
     const isWorkspaceChatType = chatType && isWorkspaceChat(chatType);
     const participants = participantList.reduce((reportParticipants: Participants, accountID: number) => {
         const participant: ReportParticipant = {
             notificationPreference,
-            ...(!isWorkspaceChatType && {role: accountID === deprecatedCurrentUserAccountID ? CONST.REPORT.ROLE.ADMIN : CONST.REPORT.ROLE.MEMBER}),
+            ...(!isWorkspaceChatType && {role: accountID === currentUserAccountID ? CONST.REPORT.ROLE.ADMIN : CONST.REPORT.ROLE.MEMBER}),
         };
         // eslint-disable-next-line no-param-reassign
         reportParticipants[accountID] = participant;
diff --git a/src/libs/actions/IOU/PerDiem.ts b/src/libs/actions/IOU/PerDiem.ts
index f358aead8ec58..9dd822bfd1401 100644
--- a/src/libs/actions/IOU/PerDiem.ts
+++ b/src/libs/actions/IOU/PerDiem.ts
@@ -356,6 +356,7 @@ function getPerDiemExpenseInformation(perDiemExpenseInformation: PerDiemExpenseI
         isNewChatReport = true;
         chatReport = buildOptimisticChatReport({
             participantList: [payerAccountID, payeeAccountID],
+            currentUserAccountID: currentUserAccountIDParam,
         });
     }
 
diff --git a/src/libs/actions/IOU/SendInvoice.ts b/src/libs/actions/IOU/SendInvoice.ts
index deffc971dfa7e..1d7e6ee883502 100644
--- a/src/libs/actions/IOU/SendInvoice.ts
+++ b/src/libs/actions/IOU/SendInvoice.ts
@@ -619,6 +619,7 @@ function getSendInvoiceInformation({
             participantList: [receiverAccountID, currentUserAccountID],
             chatType: CONST.REPORT.CHAT_TYPE.INVOICE,
             policyID: senderWorkspaceID,
+            currentUserAccountID,
         });
     }
 
diff --git a/src/libs/actions/IOU/SendMoney.ts b/src/libs/actions/IOU/SendMoney.ts
index 381ef30260d69..590d3cc088fd4 100644
--- a/src/libs/actions/IOU/SendMoney.ts
+++ b/src/libs/actions/IOU/SendMoney.ts
@@ -72,6 +72,7 @@ function getSendMoneyParams({
     created,
     merchant,
     receipt,
+    currentUserAccountID,
 }: {
     report: OnyxEntry<OnyxTypes.Report>;
     quickAction: OnyxEntry<OnyxTypes.QuickAction>;
@@ -84,6 +85,7 @@ function getSendMoneyParams({
     created?: string;
     merchant?: string;
     receipt?: Receipt;
+    currentUserAccountID: number;
 }): SendMoneyParamsData {
     const recipientEmail = addSMSDomainIfPhoneNumber(recipient.login ?? '');
     const recipientAccountID = Number(recipient.accountID);
@@ -104,6 +106,7 @@ function getSendMoneyParams({
     if (!chatReport) {
         chatReport = buildOptimisticChatReport({
             participantList: [recipientAccountID, managerID],
+            currentUserAccountID,
         });
         isNewChat = true;
     }
@@ -503,6 +506,7 @@ function sendMoneyElsewhere(
         created,
         merchant,
         receipt,
+        currentUserAccountID,
     });
     startSpan(CONST.TELEMETRY.SPAN_SUBMIT_TO_DESTINATION_VISIBLE, {
         name: 'submit-to-destination-visible',
@@ -550,6 +554,7 @@ function sendMoneyWithWallet(
         created,
         merchant,
         receipt,
+        currentUserAccountID,
     });
     startSpan(CONST.TELEMETRY.SPAN_SUBMIT_TO_DESTINATION_VISIBLE, {
         name: 'submit-to-destination-visible',
diff --git a/src/libs/actions/IOU/Split.ts b/src/libs/actions/IOU/Split.ts
index 8fb23c4d86445..2a9368a72c8d5 100644
--- a/src/libs/actions/IOU/Split.ts
+++ b/src/libs/actions/IOU/Split.ts
@@ -860,6 +860,7 @@ function completeSplitBill(
                 existingChatReport ??
                 buildOptimisticChatReport({
                     participantList: participant.accountID ? [participant.accountID, sessionAccountID] : [],
+                    currentUserAccountID: sessionAccountID,
                 });
         }
 
diff --git a/src/libs/actions/IOU/index.ts b/src/libs/actions/IOU/index.ts
index 7b22962ecd85a..cf8e85951900d 100644
--- a/src/libs/actions/IOU/index.ts
+++ b/src/libs/actions/IOU/index.ts
@@ -3326,6 +3326,7 @@ function getMoneyRequestInformation(moneyRequestInformation: MoneyRequestInforma
         chatReport = buildOptimisticChatReport({
             participantList: [payerAccountID, payeeAccountID],
             optimisticReportID: optimisticChatReportID,
+            currentUserAccountID: currentUserAccountIDParam,
         });
     }
 
@@ -7034,6 +7035,7 @@ function getOrCreateOptimisticSplitChatReport(existingSplitChatReportID: string
             reportName: '',
             chatType: CONST.REPORT.CHAT_TYPE.GROUP,
             notificationPreference: CONST.REPORT.NOTIFICATION_PREFERENCE.ALWAYS,
+            currentUserAccountID,
         });
 
         return {existingSplitChatReport: null, splitChatReport};
@@ -7042,6 +7044,7 @@ function getOrCreateOptimisticSplitChatReport(existingSplitChatReportID: string
     // Otherwise, create a new 1:1 chat report
     const splitChatReport = buildOptimisticChatReport({
         participantList: participantAccountIDs,
+        currentUserAccountID,
     });
     return {existingSplitChatReport: null, splitChatReport};
 }
@@ -7361,6 +7364,7 @@ function createSplitsAndOnyxData({
                 existingChatReport ??
                 buildOptimisticChatReport({
                     participantList: [accountID, currentUserAccountID],
+                    currentUserAccountID,
                 });
         }
 
diff --git a/src/libs/actions/Policy/Policy.ts b/src/libs/actions/Policy/Policy.ts
index 6217dbbcdae69..e91eed2c5ca5b 100644
--- a/src/libs/actions/Policy/Policy.ts
+++ b/src/libs/actions/Policy/Policy.ts
@@ -1600,6 +1600,7 @@ function createPolicyExpenseChats(
             policyID,
             ownerAccountID: cleanAccountID,
             notificationPreference,
+            currentUserAccountID: deprecatedSessionAccountID,
         });
 
         // Set correct notification preferences: visible for the submitter, hidden for others until there's activity
diff --git a/src/libs/actions/Report/index.ts b/src/libs/actions/Report/index.ts
index 0c7779bf56c41..1f3f0161c52c5 100644
--- a/src/libs/actions/Report/index.ts
+++ b/src/libs/actions/Report/index.ts
@@ -1873,6 +1873,7 @@ function getOptimisticChatReport(accountID: number, currentUserAccountID: number
     return buildOptimisticChatReport({
         participantList: [accountID, currentUserAccountID],
         notificationPreference: CONST.REPORT.NOTIFICATION_PREFERENCE.ALWAYS,
+        currentUserAccountID,
     });
 }
 
@@ -1986,6 +1987,7 @@ function navigateToAndOpenReport(
         newChat = buildOptimisticChatReport({
             participantList: [...participantAccountIDs, currentUserAccountID],
             notificationPreference: CONST.REPORT.NOTIFICATION_PREFERENCE.HIDDEN,
+            currentUserAccountID,
         });
         // We want to pass newChat here because if anything is passed in that param (even an existing chat), we will try to create a chat on the server
         openReport({reportID: newChat?.reportID, introSelected, reportActionID: '', participantLoginList: userLogins, newReportObject: newChat, isSelfTourViewed, betas});
@@ -2027,6 +2029,7 @@ function navigateToAndOpenReportWithAccountIDs(participantAccountIDs: number[],
     if (!chat) {
         newChat = buildOptimisticChatReport({
             participantList: [...participantAccountIDs, currentUserAccountID],
+            currentUserAccountID,
         });
         // We want to pass newChat here because if anything is passed in that param (even an existing chat), we will try to create a chat on the server
         openReport({
@@ -2092,6 +2095,7 @@ function createChildReport(
         parentReportActionID: parentReportAction.reportActionID,
         parentReportID: parentReport?.reportID,
         optimisticReportID: parentReportAction.childReportID,
+        currentUserAccountID,
     });
 
     const childReportID = childReport?.reportID ?? parentReportAction.childReportID;
@@ -2993,6 +2997,7 @@ function toggleSubscribeToChildReport(
             notificationPreference: CONST.REPORT.NOTIFICATION_PREFERENCE.ALWAYS,
             parentReportActionID: parentReportAction.reportActionID,
             parentReportID: parentReport?.reportID,
+            currentUserAccountID,
         });
 
         const participantLogins = PersonalDetailsUtils.getLoginsByAccountIDs(participantAccountIDs);
diff --git a/src/libs/actions/Task.ts b/src/libs/actions/Task.ts
index cb643bb224901..5011db30bbb66 100644
--- a/src/libs/actions/Task.ts
+++ b/src/libs/actions/Task.ts
@@ -924,6 +924,7 @@ function setNewOptimisticAssignee(currentUserAccountID: number, assigneePersonal
         policyID: CONST.POLICY.OWNER_EMAIL_FAKE,
         ownerAccountID: CONST.POLICY.OWNER_ACCOUNT_ID_FAKE,
         notificationPreference: CONST.REPORT.NOTIFICATION_PREFERENCE.HIDDEN,
+        currentUserAccountID,
     });
 
     Onyx.set(`${ONYXKEYS.COLLECTION.REPORT}${report.reportID}`, report);
diff --git a/src/libs/actions/TeachersUnite.ts b/src/libs/actions/TeachersUnite.ts
index 3e838ae157de0..c46cb86988ca3 100644
--- a/src/libs/actions/TeachersUnite.ts
+++ b/src/libs/actions/TeachersUnite.ts
@@ -23,12 +23,13 @@ type ExpenseReportActionData = Record<string, OptimisticCreatedReportAction>;
 /**
  * @param publicRoomReportID - This is the global reportID for the public room, we'll ignore the optimistic one
  */
-function referTeachersUniteVolunteer(partnerUserID: string, firstName: string, lastName: string, policyID: string, publicRoomReportID: string) {
+function referTeachersUniteVolunteer(partnerUserID: string, firstName: string, lastName: string, policyID: string, publicRoomReportID: string, currentUserAccountID: number) {
     const optimisticPublicRoom = buildOptimisticChatReport({
         participantList: [],
         reportName: CONST.TEACHERS_UNITE.PUBLIC_ROOM_NAME,
         chatType: CONST.REPORT.CHAT_TYPE.POLICY_ROOM,
         policyID,
+        currentUserAccountID,
     });
     const optimisticData: Array<OnyxUpdate<typeof ONYXKEYS.COLLECTION.REPORT | typeof ONYXKEYS.COLLECTION.REPORT_METADATA>> = [
         {
@@ -86,6 +87,7 @@ function addSchoolPrincipal(
         isOwnPolicyExpenseChat: true,
         oldPolicyName: policyName,
         optimisticReportID,
+        currentUserAccountID: sessionAccountID,
     });
     const expenseChatReportID = expenseChatData.reportID;
     const expenseReportCreatedAction = buildOptimisticCreatedReportAction(sessionEmail);
diff --git a/src/pages/TeachersUnite/KnowATeacherPage.tsx b/src/pages/TeachersUnite/KnowATeacherPage.tsx
index 15e149520ff86..bca5edab92401 100644
--- a/src/pages/TeachersUnite/KnowATeacherPage.tsx
+++ b/src/pages/TeachersUnite/KnowATeacherPage.tsx
@@ -8,6 +8,7 @@ import HeaderWithBackButton from '@components/HeaderWithBackButton';
 import ScreenWrapper from '@components/ScreenWrapper';
 import Text from '@components/Text';
 import TextInput from '@components/TextInput';
+import useCurrentUserPersonalDetails from '@hooks/useCurrentUserPersonalDetails';
 import useEnvironment from '@hooks/useEnvironment';
 import useLocalize from '@hooks/useLocalize';
 import useOnyx from '@hooks/useOnyx';
@@ -27,6 +28,7 @@ function KnowATeacherPage() {
     const {isProduction} = useEnvironment();
     const [loginList] = useOnyx(ONYXKEYS.LOGIN_LIST);
     const [countryCode = CONST.DEFAULT_COUNTRY_CODE] = useOnyx(ONYXKEYS.COUNTRY_CODE);
+    const {accountID: currentUserAccountID} = useCurrentUserPersonalDetails();
     /**
      * Submit form to pass firstName, partnerUserID and lastName
      */
@@ -39,7 +41,7 @@ function KnowATeacherPage() {
 
         const policyID = isProduction ? CONST.TEACHERS_UNITE.PROD_POLICY_ID : CONST.TEACHERS_UNITE.TEST_POLICY_ID;
         const publicRoomReportID = isProduction ? CONST.TEACHERS_UNITE.PROD_PUBLIC_ROOM_ID : CONST.TEACHERS_UNITE.TEST_PUBLIC_ROOM_ID;
-        TeachersUnite.referTeachersUniteVolunteer(contactMethod, firstName, lastName, policyID, publicRoomReportID);
+        TeachersUnite.referTeachersUniteVolunteer(contactMethod, firstName, lastName, policyID, publicRoomReportID, currentUserAccountID);
     };
 
     /**
diff --git a/src/pages/workspace/WorkspaceNewRoomPage.tsx b/src/pages/workspace/WorkspaceNewRoomPage.tsx
index 22c009ce2832a..6f0e88ae2c190 100644
--- a/src/pages/workspace/WorkspaceNewRoomPage.tsx
+++ b/src/pages/workspace/WorkspaceNewRoomPage.tsx
@@ -118,7 +118,8 @@ function WorkspaceNewRoomPage({ref}: WorkspaceNewRoomPageProps) {
      */
     const submit = (values: FormOnyxValues<typeof ONYXKEYS.FORMS.NEW_ROOM_FORM>) => {
         setNewRoomFormLoading();
-        const participants = [session?.accountID ?? CONST.DEFAULT_NUMBER_ID];
+        const currentUserAccountID = session?.accountID ?? CONST.DEFAULT_NUMBER_ID;
+        const participants = [currentUserAccountID];
         const parsedDescription = getParsedComment(values.reportDescription ?? '', {policyID});
         const policyReport = buildOptimisticChatReport({
             participantList: participants,
@@ -130,6 +131,7 @@ function WorkspaceNewRoomPage({ref}: WorkspaceNewRoomPageProps) {
             writeCapability: writeCapability || CONST.REPORT.WRITE_CAPABILITIES.ALL,
             notificationPreference: CONST.REPORT.NOTIFICATION_PREFERENCE.DAILY,
             description: parsedDescription,
+            currentUserAccountID,
         });
 
         // eslint-disable-next-line @typescript-eslint/no-deprecated
diff --git a/tests/unit/ReportUtilsTest.ts b/tests/unit/ReportUtilsTest.ts
index 1b2bf20b294b5..3318f39e5e89b 100644
--- a/tests/unit/ReportUtilsTest.ts
+++ b/tests/unit/ReportUtilsTest.ts
@@ -6263,9 +6263,53 @@ describe('ReportUtils', () => {
         it('should always set isPinned to false', () => {
             const result = buildOptimisticChatReport({
                 participantList: [1, 2, 3],
+                currentUserAccountID: 1,
             });
             expect(result.isPinned).toBe(false);
         });
+
+        it('should assign ADMIN role to currentUserAccountID and MEMBER role to others for non-workspace chats', () => {
+            const currentUser = 100;
+            const result = buildOptimisticChatReport({
+                participantList: [currentUser, 200, 300],
+                currentUserAccountID: currentUser,
+            });
+            expect(result.participants?.[currentUser]?.role).toBe(CONST.REPORT.ROLE.ADMIN);
+            expect(result.participants?.[200]?.role).toBe(CONST.REPORT.ROLE.MEMBER);
+            expect(result.participants?.[300]?.role).toBe(CONST.REPORT.ROLE.MEMBER);
+        });
+
+        it('should assign ADMIN role based on the provided currentUserAccountID, not the deprecated global value', () => {
+            const explicitCurrentUser = 999;
+            const result = buildOptimisticChatReport({
+                participantList: [explicitCurrentUser, 1, 2],
+                currentUserAccountID: explicitCurrentUser,
+            });
+            expect(result.participants?.[explicitCurrentUser]?.role).toBe(CONST.REPORT.ROLE.ADMIN);
+            expect(result.participants?.[1]?.role).toBe(CONST.REPORT.ROLE.MEMBER);
+            expect(result.participants?.[2]?.role).toBe(CONST.REPORT.ROLE.MEMBER);
+        });
+
+        it('should not assign role for workspace chat types', () => {
+            const currentUser = 100;
+            const result = buildOptimisticChatReport({
+                participantList: [currentUser, 200],
+                chatType: CONST.REPORT.CHAT_TYPE.POLICY_EXPENSE_CHAT,
+                currentUserAccountID: currentUser,
+            });
+            expect(result.participants?.[currentUser]?.role).toBeUndefined();
+            expect(result.participants?.[200]?.role).toBeUndefined();
+        });
+
+        it('should assign all participants as MEMBER when currentUserAccountID is not in the participant list', () => {
+            const result = buildOptimisticChatReport({
+                participantList: [1, 2, 3],
+                currentUserAccountID: 999,
+            });
+            expect(result.participants?.[1]?.role).toBe(CONST.REPORT.ROLE.MEMBER);
+            expect(result.participants?.[2]?.role).toBe(CONST.REPORT.ROLE.MEMBER);
+            expect(result.participants?.[3]?.role).toBe(CONST.REPORT.ROLE.MEMBER);
+        });
     });
 
     describe('getWorkspaceNameUpdatedMessage', () => {