diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3f347914c..4c1751763 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## Unreleased
+
+### Fixed
+
+- Fixed the time in market of the portfolio summary to be empty if there is no activity
+
 ## 3.35.0 - 2026-07-27
 
 ### Added
diff --git a/apps/api/src/app/portfolio/calculator/portfolio-calculator.ts b/apps/api/src/app/portfolio/calculator/portfolio-calculator.ts
index 80968ebd1..38f942156 100644
--- a/apps/api/src/app/portfolio/calculator/portfolio-calculator.ts
+++ b/apps/api/src/app/portfolio/calculator/portfolio-calculator.ts
@@ -816,25 +816,39 @@ export abstract class PortfolioCalculator {
     let firstAccountBalanceDate: Date;
     let firstActivityDate: Date;
 
-    try {
-      const firstAccountBalanceDateString = this.accountBalanceItems[0]?.date;
-      firstAccountBalanceDate = firstAccountBalanceDateString
-        ? parseDate(firstAccountBalanceDateString)
-        : new Date();
-    } catch (error) {
-      firstAccountBalanceDate = new Date();
+    if (this.accountBalanceItems?.length > 0) {
+      try {
+        const firstAccountBalanceDateString = this.accountBalanceItems[0].date;
+        firstAccountBalanceDate = firstAccountBalanceDateString
+          ? parseDate(firstAccountBalanceDateString)
+          : new Date();
+      } catch (error) {
+        firstAccountBalanceDate = new Date();
+      }
     }
 
-    try {
-      const firstActivityDateString = this.transactionPoints[0].date;
-      firstActivityDate = firstActivityDateString
-        ? parseDate(firstActivityDateString)
-        : new Date();
-    } catch (error) {
-      firstActivityDate = new Date();
+    if (this.transactionPoints?.length > 0) {
+      try {
+        const firstActivityDateString = this.transactionPoints[0].date;
+        firstActivityDate = firstActivityDateString
+          ? parseDate(firstActivityDateString)
+          : new Date();
+      } catch (error) {
+        firstActivityDate = new Date();
+      }
+    }
+
+    const dates = [firstAccountBalanceDate, firstActivityDate].filter(
+      (date) => {
+        return !!date;
+      }
+    );
+
+    if (dates.length === 0) {
+      return undefined;
     }
 
-    return min([firstAccountBalanceDate, firstActivityDate]);
+    return min(dates);
   }
 
   protected abstract getSymbolMetrics({
diff --git a/apps/api/src/app/portfolio/portfolio.service.ts b/apps/api/src/app/portfolio/portfolio.service.ts
index 2eae63544..6a3c1f145 100644
--- a/apps/api/src/app/portfolio/portfolio.service.ts
+++ b/apps/api/src/app/portfolio/portfolio.service.ts
@@ -1986,7 +1986,9 @@ export class PortfolioService {
       .minus(liabilities)
       .toNumber();
 
-    const daysInMarket = differenceInDays(new Date(), dateOfFirstActivity);
+    const daysInMarket = dateOfFirstActivity
+      ? differenceInDays(new Date(), dateOfFirstActivity)
+      : 0;
 
     const annualizedPerformancePercent = getAnnualizedPerformancePercent({
       daysInMarket,
diff --git a/apps/client/src/app/components/portfolio-summary/portfolio-summary.component.ts b/apps/client/src/app/components/portfolio-summary/portfolio-summary.component.ts
index 8bc79b624..1cd2ec93c 100644
--- a/apps/client/src/app/components/portfolio-summary/portfolio-summary.component.ts
+++ b/apps/client/src/app/components/portfolio-summary/portfolio-summary.component.ts
@@ -116,7 +116,7 @@ export class GfPortfolioSummaryComponent implements OnChanges {
           }
         );
       } else {
-        this.timeInMarket = '-';
+        this.timeInMarket = '–';
       }
     } else {
       this.timeInMarket = undefined;
diff --git a/libs/common/src/lib/interfaces/portfolio-summary.interface.ts b/libs/common/src/lib/interfaces/portfolio-summary.interface.ts
index e109a7e63..b1b7e938b 100644
--- a/libs/common/src/lib/interfaces/portfolio-summary.interface.ts
+++ b/libs/common/src/lib/interfaces/portfolio-summary.interface.ts
@@ -6,7 +6,7 @@ export interface PortfolioSummary extends PortfolioPerformance {
   annualizedPerformancePercent: number;
   annualizedPerformancePercentWithCurrencyEffect: number;
   cash: number;
-  dateOfFirstActivity: Date;
+  dateOfFirstActivity?: Date;
   dividendInBaseCurrency: number;
   emergencyFund: {
     assets: number;