diff --git a/src/libs/API/parameters/MergeDuplicatesParams.ts b/src/libs/API/parameters/MergeDuplicatesParams.ts
index 7f2c3daa7eaf..8edbfa0e8cac 100644
--- a/src/libs/API/parameters/MergeDuplicatesParams.ts
+++ b/src/libs/API/parameters/MergeDuplicatesParams.ts
@@ -10,7 +10,7 @@ type MergeDuplicatesParams = {
     billable: boolean;
     reimbursable: boolean;
     tag: string;
-    taxCode: string;
+    taxCode?: string;
     receiptID: number;
     reportID: string | undefined;
     reportActionID?: string | undefined;
diff --git a/src/libs/TransactionUtils/index.ts b/src/libs/TransactionUtils/index.ts
index 6a994ee91cba..b071ea538af2 100644
--- a/src/libs/TransactionUtils/index.ts
+++ b/src/libs/TransactionUtils/index.ts
@@ -2559,8 +2559,8 @@ function buildNewTransactionAfterReviewingDuplicates(reviewDuplicateTransaction:
         modifiedMerchant: reviewDuplicateTransaction?.merchant,
         merchant: reviewDuplicateTransaction?.merchant,
         comment: {...reviewDuplicateTransaction?.comment, comment: reviewDuplicateTransaction?.description},
-        // Clear stale taxName/taxValue so MoneyRequestView derives them fresh from the policy using the updated taxCode
-        ...(reviewDuplicateTransaction?.taxCode !== undefined && {taxName: undefined, taxValue: undefined}),
+        // If the taxCode changes, clear stale taxName/taxValue so MoneyRequestView derives them fresh from the policy using the updated taxCode
+        ...(reviewDuplicateTransaction?.taxCode !== undefined && reviewDuplicateTransaction?.taxCode !== duplicatedTransaction?.taxCode && {taxName: undefined, taxValue: undefined}),
     };
 }
 
@@ -2581,7 +2581,6 @@ function buildMergeDuplicatesParams(
         reimbursable: reviewDuplicates?.reimbursable ?? false,
         category: reviewDuplicates?.category ?? '',
         tag: reviewDuplicates?.tag ?? '',
-        taxCode: reviewDuplicates?.taxCode ?? '',
         merchant: reviewDuplicates?.merchant ?? '',
         comment: reviewDuplicates?.description ?? '',
     };
diff --git a/src/libs/actions/IOU/Duplicate.ts b/src/libs/actions/IOU/Duplicate.ts
index c263b6032277..fda4aedeedbf 100644
--- a/src/libs/actions/IOU/Duplicate.ts
+++ b/src/libs/actions/IOU/Duplicate.ts
@@ -75,7 +75,7 @@ function getIOUActionForTransactions(transactionIDList: Array<string | undefined
 }
 
 /** Merge several transactions into one by updating the fields of the one we want to keep and deleting the rest */
-function mergeDuplicates({transactionThreadReportID: optimisticTransactionThreadReportID, taxAmount, taxValue, ...params}: MergeDuplicatesParams & {taxAmount: number; taxValue: string}) {
+function mergeDuplicates({transactionThreadReportID: optimisticTransactionThreadReportID, taxAmount, taxValue, ...params}: MergeDuplicatesParams & {taxAmount?: number; taxValue?: string}) {
     const allParams: MergeDuplicatesParams = {...params};
     const allTransactions = getAllTransactions();
     const allTransactionViolations = getAllTransactionViolations();
@@ -100,9 +100,9 @@ function mergeDuplicates({transactionThreadReportID: optimisticTransactionThread
             modifiedMerchant: params.merchant,
             reimbursable: params.reimbursable,
             tag: params.tag,
-            taxCode: params.taxCode,
-            taxAmount,
-            taxValue,
+            taxCode: params.taxCode ?? originalSelectedTransaction?.taxCode,
+            taxAmount: taxAmount ?? originalSelectedTransaction?.taxAmount,
+            taxValue: taxValue ?? originalSelectedTransaction?.taxValue,
         },
     };
 
@@ -351,7 +351,7 @@ function mergeDuplicates({transactionThreadReportID: optimisticTransactionThread
 }
 
 /** Instead of merging the duplicates, it updates the transaction we want to keep and puts the others on hold without deleting them */
-function resolveDuplicates({taxAmount, taxValue, ...params}: MergeDuplicatesParams & {taxAmount: number; taxValue: string}) {
+function resolveDuplicates({taxAmount, taxValue, ...params}: MergeDuplicatesParams & {taxAmount?: number; taxValue?: string}) {
     if (!params.transactionID) {
         return;
     }
@@ -376,9 +376,9 @@ function resolveDuplicates({taxAmount, taxValue, ...params}: MergeDuplicatesPara
             modifiedMerchant: params.merchant,
             reimbursable: params.reimbursable,
             tag: params.tag,
-            taxCode: params.taxCode,
-            taxAmount,
-            taxValue,
+            taxCode: params.taxCode ?? originalSelectedTransaction?.taxCode,
+            taxAmount: taxAmount ?? originalSelectedTransaction?.taxAmount,
+            taxValue: taxValue ?? originalSelectedTransaction?.taxValue,
         },
     };
 
diff --git a/src/pages/TransactionDuplicate/Confirmation.tsx b/src/pages/TransactionDuplicate/Confirmation.tsx
index a9ef6b8bc2d2..40dd511a89bc 100644
--- a/src/pages/TransactionDuplicate/Confirmation.tsx
+++ b/src/pages/TransactionDuplicate/Confirmation.tsx
@@ -57,6 +57,7 @@ function Confirmation() {
     const [reviewDuplicatesReport] = useOnyx(`${ONYXKEYS.COLLECTION.REPORT}${reviewDuplicates?.reportID}`);
     const [policyCategories] = useOnyx(`${ONYXKEYS.COLLECTION.POLICY_CATEGORIES}${getNonEmptyStringOnyxID(reviewDuplicatesReport?.policyID)}`);
     const [policy] = useOnyx(`${ONYXKEYS.COLLECTION.POLICY}${report?.policyID}`);
+    const [duplicatedTransactionPolicy] = useOnyx(`${ONYXKEYS.COLLECTION.POLICY}${getNonEmptyStringOnyxID(reviewDuplicatesReport?.policyID)}`);
     const [policyTags] = useOnyx(`${ONYXKEYS.COLLECTION.POLICY_TAGS}${getNonEmptyStringOnyxID(reviewDuplicatesReport?.policyID)}`);
     const compareResult = TransactionUtils.compareDuplicateTransactionFields(policyTags ?? {}, transaction, allDuplicates, reviewDuplicatesReport, undefined, policy, policyCategories);
     const {goBack} = useReviewDuplicatesNavigation(Object.keys(compareResult.change ?? {}), 'confirmation', route.params.threadReportID, route.params.backTo);
@@ -75,12 +76,18 @@ function Confirmation() {
     );
     const taxData = useMemo(() => {
         const taxCode = reviewDuplicates?.taxCode ?? '';
-        const taxRate = taxCode ? policy?.taxRates?.taxes?.[taxCode] : undefined;
+        const taxRate = taxCode ? duplicatedTransactionPolicy?.taxRates?.taxes?.[taxCode] : undefined;
+        // Preserve taxAmount and taxValue if taxCode is deleted or remains unchanged compared to duplicatedTransaction?.taxCode.
+        if (!taxRate || (taxCode && duplicatedTransaction?.taxCode === taxCode) || reviewDuplicates?.taxAmount === undefined) {
+            return;
+        }
+
         return {
-            taxAmount: -(reviewDuplicates?.taxAmount ?? 0),
-            taxValue: taxRate?.value ?? '',
+            taxAmount: -reviewDuplicates.taxAmount,
+            taxValue: taxRate?.value,
+            taxCode,
         };
-    }, [reviewDuplicates?.taxCode, reviewDuplicates?.taxAmount, policy?.taxRates?.taxes]);
+    }, [reviewDuplicates?.taxCode, reviewDuplicates?.taxAmount, duplicatedTransactionPolicy?.taxRates?.taxes, duplicatedTransaction?.taxCode]);
     const isReportOwner = iouReport?.ownerAccountID === currentUserPersonalDetails?.accountID;
 
     const handleMergeDuplicates = useCallback(() => {
diff --git a/src/pages/TransactionDuplicate/ReviewTaxCode.tsx b/src/pages/TransactionDuplicate/ReviewTaxCode.tsx
index 96dd7a8405e3..bcca68cbd62c 100644
--- a/src/pages/TransactionDuplicate/ReviewTaxCode.tsx
+++ b/src/pages/TransactionDuplicate/ReviewTaxCode.tsx
@@ -31,6 +31,7 @@ function ReviewTaxRate() {
     const [transactionThreadReport] = useOnyx(`${ONYXKEYS.COLLECTION.REPORT}${route.params.threadReportID}`);
     const transactionID = getTransactionID(transactionThreadReport);
     const [transaction] = useOnyx(`${ONYXKEYS.COLLECTION.TRANSACTION}${getNonEmptyStringOnyxID(transactionID)}`);
+    const [duplicatedTransaction] = useOnyx(`${ONYXKEYS.COLLECTION.TRANSACTION}${getNonEmptyStringOnyxID(reviewDuplicates?.transactionID)}`);
     const [transactionViolations] = useOnyx(`${ONYXKEYS.COLLECTION.TRANSACTION_VIOLATIONS}${transactionID}`);
     const allDuplicateIDs = useMemo(
         () => transactionViolations?.find((violation) => violation.name === CONST.VIOLATIONS.DUPLICATED_TRANSACTION)?.data?.duplicates ?? [],
@@ -64,11 +65,15 @@ function ReviewTaxRate() {
     );
     const getTaxAmount = useCallback(
         (taxID: string) => {
+            // If the tax code remains unchanged, preserve the tax amount to avoid resetting it to the default value when resolving duplicates.
+            if (taxID === duplicatedTransaction?.taxCode) {
+                return;
+            }
             const taxPercentage = getTaxValue(policy, transaction, taxID);
             const decimals = getCurrencyDecimals(transaction?.currency);
             return convertToBackendAmount(calculateTaxAmount(taxPercentage ?? '', getAmount(transaction), decimals));
         },
-        [policy, transaction, getCurrencyDecimals],
+        [policy, transaction, getCurrencyDecimals, duplicatedTransaction?.taxCode],
     );
 
     const setTaxCode = useCallback(