diff --git a/CHANGELOG.md b/CHANGELOG.md
index ad8f2f70e..954396b49 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -22,6 +22,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Fixed
 
 - Ensured the locale is available in the settings dialog to customize the rule thresholds of the _X-ray_ page
+- Ensured atomic data replacememt for historical market data fetching
 
 ## 2.211.0 - 2025-10-25
 
diff --git a/apps/api/src/services/interfaces/interfaces.ts b/apps/api/src/services/interfaces/interfaces.ts
index 7469754b5..0c7cd31c0 100644
--- a/apps/api/src/services/interfaces/interfaces.ts
+++ b/apps/api/src/services/interfaces/interfaces.ts
@@ -20,4 +20,5 @@ export interface DataProviderResponse {
 
 export interface DataGatheringItem extends AssetProfileIdentifier {
   date?: Date;
+  replaceExistingData?: boolean;
 }
diff --git a/apps/api/src/services/market-data/market-data.service.ts b/apps/api/src/services/market-data/market-data.service.ts
index 38ad61663..e046bc8dd 100644
--- a/apps/api/src/services/market-data/market-data.service.ts
+++ b/apps/api/src/services/market-data/market-data.service.ts
@@ -205,4 +205,41 @@ export class MarketDataService {
 
     return this.prismaService.$transaction(upsertPromises);
   }
+
+  /**
+   * Atomically replace all market data for a symbol.
+   * Deletes existing data and inserts new data within a single transaction
+   * to prevent data loss if the operation fails.
+   */
+  public async replaceAllForSymbol({
+    dataSource,
+    symbol,
+    data
+  }: {
+    dataSource: DataSource;
+    symbol: string;
+    data: Prisma.MarketDataUpdateInput[];
+  }): Promise<void> {
+    await this.prismaService.$transaction(async (prisma) => {
+      await prisma.marketData.deleteMany({
+        where: {
+          dataSource,
+          symbol
+        }
+      });
+
+      if (data.length > 0) {
+        await prisma.marketData.createMany({
+          data: data.map(({ dataSource, date, marketPrice, state }) => ({
+            dataSource: dataSource as DataSource,
+            date: date as Date,
+            marketPrice: marketPrice as number,
+            state: state as MarketDataState,
+            symbol: symbol as string
+          })),
+          skipDuplicates: true
+        });
+      }
+    });
+  }
 }
diff --git a/apps/api/src/services/queues/data-gathering/data-gathering.processor.ts b/apps/api/src/services/queues/data-gathering/data-gathering.processor.ts
index 1a172f3ea..57c99a87c 100644
--- a/apps/api/src/services/queues/data-gathering/data-gathering.processor.ts
+++ b/apps/api/src/services/queues/data-gathering/data-gathering.processor.ts
@@ -100,7 +100,7 @@ export class DataGatheringProcessor {
     name: GATHER_HISTORICAL_MARKET_DATA_PROCESS_JOB_NAME
   })
   public async gatherHistoricalMarketData(job: Job<DataGatheringItem>) {
-    const { dataSource, date, symbol } = job.data;
+    const { dataSource, date, symbol, replaceExistingData } = job.data;
 
     try {
       let currentDate = parseISO(date as unknown as string);
@@ -109,7 +109,7 @@ export class DataGatheringProcessor {
         `Historical market data gathering has been started for ${symbol} (${dataSource}) at ${format(
           currentDate,
           DATE_FORMAT
-        )}`,
+        )}${replaceExistingData ? ' (replace mode)' : ''}`,
         `DataGatheringProcessor (${GATHER_HISTORICAL_MARKET_DATA_PROCESS_JOB_NAME})`
       );
 
@@ -157,7 +157,15 @@ export class DataGatheringProcessor {
         currentDate = addDays(currentDate, 1);
       }
 
-      await this.marketDataService.updateMany({ data });
+      if (replaceExistingData) {
+        await this.marketDataService.replaceAllForSymbol({
+          dataSource,
+          symbol,
+          data
+        });
+      } else {
+        await this.marketDataService.updateMany({ data });
+      }
 
       Logger.log(
         `Historical market data gathering has been completed for ${symbol} (${dataSource}) at ${format(
diff --git a/apps/api/src/services/queues/data-gathering/data-gathering.service.ts b/apps/api/src/services/queues/data-gathering/data-gathering.service.ts
index 2d3ec45ad..7bcde097c 100644
--- a/apps/api/src/services/queues/data-gathering/data-gathering.service.ts
+++ b/apps/api/src/services/queues/data-gathering/data-gathering.service.ts
@@ -2,7 +2,6 @@ import { DataProviderService } from '@ghostfolio/api/services/data-provider/data
 import { DataEnhancerInterface } from '@ghostfolio/api/services/data-provider/interfaces/data-enhancer.interface';
 import { ExchangeRateDataService } from '@ghostfolio/api/services/exchange-rate-data/exchange-rate-data.service';
 import { DataGatheringItem } from '@ghostfolio/api/services/interfaces/interfaces';
-import { MarketDataService } from '@ghostfolio/api/services/market-data/market-data.service';
 import { PrismaService } from '@ghostfolio/api/services/prisma/prisma.service';
 import { PropertyService } from '@ghostfolio/api/services/property/property.service';
 import { SymbolProfileService } from '@ghostfolio/api/services/symbol-profile/symbol-profile.service';
@@ -41,7 +40,6 @@ export class DataGatheringService {
     private readonly dataGatheringQueue: Queue,
     private readonly dataProviderService: DataProviderService,
     private readonly exchangeRateDataService: ExchangeRateDataService,
-    private readonly marketDataService: MarketDataService,
     private readonly prismaService: PrismaService,
     private readonly propertyService: PropertyService,
     private readonly symbolProfileService: SymbolProfileService
@@ -95,8 +93,6 @@ export class DataGatheringService {
   }
 
   public async gatherSymbol({ dataSource, date, symbol }: DataGatheringItem) {
-    await this.marketDataService.deleteMany({ dataSource, symbol });
-
     const dataGatheringItems = (await this.getSymbolsMax())
       .filter((dataGatheringItem) => {
         return (
@@ -111,7 +107,8 @@ export class DataGatheringService {
 
     await this.gatherSymbols({
       dataGatheringItems,
-      priority: DATA_GATHERING_QUEUE_PRIORITY_HIGH
+      priority: DATA_GATHERING_QUEUE_PRIORITY_HIGH,
+      replaceExistingData: true
     });
   }
 
@@ -274,10 +271,12 @@ export class DataGatheringService {
 
   public async gatherSymbols({
     dataGatheringItems,
-    priority
+    priority,
+    replaceExistingData = false
   }: {
     dataGatheringItems: DataGatheringItem[];
     priority: number;
+    replaceExistingData?: boolean;
   }) {
     await this.addJobsToQueue(
       dataGatheringItems.map(({ dataSource, date, symbol }) => {
@@ -285,7 +284,8 @@ export class DataGatheringService {
           data: {
             dataSource,
             date,
-            symbol
+            symbol,
+            replaceExistingData
           },
           name: GATHER_HISTORICAL_MARKET_DATA_PROCESS_JOB_NAME,
           opts: {