diff --git a/browser/ui/webui/brave_rewards_page_ui.cc b/browser/ui/webui/brave_rewards_page_ui.cc
index a91f10602220..313ee7ec056a 100644
--- a/browser/ui/webui/brave_rewards_page_ui.cc
+++ b/browser/ui/webui/brave_rewards_page_ui.cc
@@ -1267,7 +1267,9 @@ void RewardsDOMHandler::SaveAdsSetting(const base::ListValue* args) {
   const std::string value = args->GetList()[1].GetString();
 
   if (key == "adsEnabled") {
-    ads_service_->SetEnabled(value == "true");
+    const auto is_enabled =
+        value == "true" && ads_service_->IsSupportedRegion();
+    ads_service_->SetEnabled(is_enabled);
   } else if (key == "adsPerHour") {
     ads_service_->SetAdsPerHour(std::stoull(value));
   }
diff --git a/components/brave_ads/browser/ads_service_impl.cc b/components/brave_ads/browser/ads_service_impl.cc
index 05dfe6531639..a88abb804fe8 100644
--- a/components/brave_ads/browser/ads_service_impl.cc
+++ b/components/brave_ads/browser/ads_service_impl.cc
@@ -1285,8 +1285,8 @@ void AdsServiceImpl::MigratePrefsVersion1To2() {
 }
 
 void AdsServiceImpl::MigratePrefsVersion2To3() {
-  auto locale = GetLocale();
-  auto region = ads::Ads::GetRegion(locale);
+  const auto locale = GetLocale();
+  const auto region = ads::Ads::GetRegion(locale);
 
   // Disable ads if upgrading from a pre brave ads build due to a bug where ads
   // were always enabled
@@ -1294,7 +1294,7 @@ void AdsServiceImpl::MigratePrefsVersion2To3() {
 
   // Disable ads for unsupported legacy regions due to a bug where ads were
   // enabled even if the users region was not supported
-  std::vector<std::string> legacy_regions = {
+  const std::vector<std::string> legacy_regions = {
     "US",  // United States of America
     "CA",  // Canada
     "GB",  // United Kingdom (Great Britain and Northern Ireland)
@@ -1305,7 +1305,7 @@ void AdsServiceImpl::MigratePrefsVersion2To3() {
   DisableAdsForUnsupportedRegions(region, legacy_regions);
 
   // On-board users for newly supported regions
-  std::vector<std::string> new_regions = {
+  const std::vector<std::string> new_regions = {
     "AU",  // Australia
     "NZ",  // New Zealand
     "IE"   // Ireland
@@ -1315,11 +1315,26 @@ void AdsServiceImpl::MigratePrefsVersion2To3() {
 }
 
 void AdsServiceImpl::MigratePrefsVersion3To4() {
-  auto locale = GetLocale();
-  auto region = ads::Ads::GetRegion(locale);
+  const auto locale = GetLocale();
+  const auto region = ads::Ads::GetRegion(locale);
+
+  // Disable ads for unsupported legacy regions due to a bug where ads were
+  // enabled even if the users region was not supported
+  const std::vector<std::string> legacy_regions = {
+    "US",  // United States of America
+    "CA",  // Canada
+    "GB",  // United Kingdom (Great Britain and Northern Ireland)
+    "DE",  // Germany
+    "FR",  // France
+    "AU",  // Australia
+    "NZ",  // New Zealand
+    "IE"   // Ireland
+  };
+
+  DisableAdsForUnsupportedRegions(region, legacy_regions);
 
   // On-board users for newly supported regions
-  std::vector<std::string> new_regions = {
+  const std::vector<std::string> new_regions = {
     "AR",  // Argentina
     "AT",  // Austria
     "BR",  // Brazil
@@ -1348,11 +1363,48 @@ void AdsServiceImpl::MigratePrefsVersion3To4() {
 }
 
 void AdsServiceImpl::MigratePrefsVersion4To5() {
-  auto locale = GetLocale();
-  auto region = ads::Ads::GetRegion(locale);
+  const auto locale = GetLocale();
+  const auto region = ads::Ads::GetRegion(locale);
+
+  // Disable ads for unsupported legacy regions due to a bug where ads were
+  // enabled even if the users region was not supported
+  const std::vector<std::string> legacy_regions = {
+    "US",  // United States of America
+    "CA",  // Canada
+    "GB",  // United Kingdom (Great Britain and Northern Ireland)
+    "DE",  // Germany
+    "FR",  // France
+    "AU",  // Australia
+    "NZ",  // New Zealand
+    "IE",  // Ireland
+    "AR",  // Argentina
+    "AT",  // Austria
+    "BR",  // Brazil
+    "CH",  // Switzerland
+    "CL",  // Chile
+    "CO",  // Colombia
+    "DK",  // Denmark
+    "EC",  // Ecuador
+    "IL",  // Israel
+    "IN",  // India
+    "IT",  // Italy
+    "JP",  // Japan
+    "KR",  // Korea
+    "MX",  // Mexico
+    "NL",  // Netherlands
+    "PE",  // Peru
+    "PH",  // Philippines
+    "PL",  // Poland
+    "SE",  // Sweden
+    "SG",  // Singapore
+    "VE",  // Venezuela
+    "ZA"   // South Africa
+  };
+
+  DisableAdsForUnsupportedRegions(region, legacy_regions);
 
   // On-board users for newly supported regions
-  std::vector<std::string> new_regions = {
+  const std::vector<std::string> new_regions = {
     "KY"   // Cayman Islands
   };
 
diff --git a/components/brave_ads/common/pref_names.cc b/components/brave_ads/common/pref_names.cc
index 3045de151e77..b71d17594242 100644
--- a/components/brave_ads/common/pref_names.cc
+++ b/components/brave_ads/common/pref_names.cc
@@ -36,7 +36,7 @@ const char kShouldShowMyFirstAdNotification[] =
 // Stores the preferences version number
 const char kVersion[] = "brave.brave_ads.prefs.version";
 
-const int kCurrentVersionNumber = 4;
+const int kCurrentVersionNumber = 5;
 
 // Ads were disabled at least once.
 const char kBraveAdsWereDisabled[] = "brave.brave_ads.were_disabled";