diff --git a/packages/client/src/runtime/getPrismaClient.ts b/packages/client/src/runtime/getPrismaClient.ts
index 5b71c916fccb..18784bbb479d 100644
--- a/packages/client/src/runtime/getPrismaClient.ts
+++ b/packages/client/src/runtime/getPrismaClient.ts
@@ -830,9 +830,6 @@ Or read our docs at https://www.prisma.io/docs/concepts/components/prisma-client
         if (activeScope !== itxContext.scopeId) {
           throw new Error('Concurrent nested transactions are not supported')
         }
-
-        // Re-use the underlying transaction in the engine by reusing the same transaction id.
-        options.newTxId = itxContext.txId
       }
       scopeStack.push(scopeId)
 
@@ -842,7 +839,8 @@ Or read our docs at https://www.prisma.io/docs/concepts/components/prisma-client
         maxWait: options?.maxWait ?? this._engineConfig.transactionOptions.maxWait,
         timeout: options?.timeout ?? this._engineConfig.transactionOptions.timeout,
         isolationLevel: options?.isolationLevel ?? this._engineConfig.transactionOptions.isolationLevel,
-        newTxId: options.newTxId,
+        // Re-use the underlying transaction in the engine by reusing the same transaction id.
+        newTxId: isNested ? itxContext.txId : undefined,
       }
       let info: Transaction.InteractiveTransactionInfo<unknown>
       try {
diff --git a/packages/client/tests/functional/interactive-transactions/tests.ts b/packages/client/tests/functional/interactive-transactions/tests.ts
index 061d4a7cd3e4..6c1bc7f53ce4 100644
--- a/packages/client/tests/functional/interactive-transactions/tests.ts
+++ b/packages/client/tests/functional/interactive-transactions/tests.ts
@@ -521,6 +521,29 @@ testMatrix.setupTestSuite(
       expect(users.map((u) => u.email)).toEqual([outerEmail1, outerEmail2].sort())
     })
 
+    testIf(provider !== Providers.MONGODB)('sql: nested transaction does not mutate the options object', async () => {
+      const email1 = `user_${copycat.uuid(251)}@website.com`
+      const email2 = `user_${copycat.uuid(252)}@website.com`
+      const options = { maxWait: 5000, timeout: 5000 }
+
+      await prisma.$transaction(async (tx) => {
+        await tx.$transaction(async (tx2) => {
+          await tx2.user.create({ data: { email: email1 } })
+        }, options)
+      }, options)
+
+      expect(options).toStrictEqual({ maxWait: 5000, timeout: 5000 })
+
+      await prisma.$transaction(async (tx) => {
+        await tx.user.create({ data: { email: email2 } })
+      }, options)
+
+      const users = await prisma.user.findMany({
+        where: { email: { in: [email1, email2] } },
+      })
+      expect(users).toHaveLength(2)
+    })
+
     testIf(provider !== Providers.MONGODB)('sql: enforce order for nested transactions', async () => {
       const result = prisma.$transaction(async (tx) => {
         const nested = tx.$transaction(async (tx2) => {