diff --git a/CHANGELOG.md b/CHANGELOG.md
index add9b2b74e..2a8f4c17f7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,12 @@
 > make sure you follow our [migration guide](https://docs.sentry.io/platforms/react-native/migration/) first.
 <!-- prettier-ignore-end -->
 
+## Unreleased
+
+### Features
+
+- Support `SENTRY_ENVIRONMENT` in bare React Native builds ([#5823](https://github.com/getsentry/sentry-react-native/pull/5823))
+
 ## 8.4.0
 
 ### Fixes
diff --git a/packages/core/scripts/sentry-xcode.sh b/packages/core/scripts/sentry-xcode.sh
index b73ffbca35..069f08be01 100755
--- a/packages/core/scripts/sentry-xcode.sh
+++ b/packages/core/scripts/sentry-xcode.sh
@@ -101,6 +101,20 @@ if [ "$SENTRY_COPY_OPTIONS_FILE" = true ]; then
     echo "[Sentry] $SENTRY_OPTIONS_FILE_PATH not found. $SENTRY_OPTIONS_FILE_ERROR_MESSAGE_POSTFIX" 1>&2
   else
     cp "$SENTRY_OPTIONS_FILE_PATH" "$SENTRY_OPTIONS_FILE_DESTINATION_PATH"
+
+    if [ -n "$SENTRY_ENVIRONMENT" ]; then
+      if "$LOCAL_NODE_BINARY" -e "
+        var fs = require('fs');
+        var destPath = process.argv[1];
+        var opts = JSON.parse(fs.readFileSync(destPath, 'utf8'));
+        opts.environment = process.env.SENTRY_ENVIRONMENT;
+        fs.writeFileSync(destPath, JSON.stringify(opts));
+      " -- "$SENTRY_OPTIONS_FILE_DESTINATION_PATH" 2>/dev/null; then
+        echo "[Sentry] Overriding 'environment' from SENTRY_ENVIRONMENT environment variable"
+      else
+        echo "[Sentry] Failed to override environment, copied file as-is." 1>&2
+      fi
+    fi
     echo "[Sentry] Copied $SENTRY_OPTIONS_FILE_PATH to $SENTRY_OPTIONS_FILE_DESTINATION_PATH"
   fi
 fi
diff --git a/packages/core/sentry.gradle b/packages/core/sentry.gradle
index 91171e9c3b..86dcc1cbbf 100644
--- a/packages/core/sentry.gradle
+++ b/packages/core/sentry.gradle
@@ -44,6 +44,19 @@ tasks.register("copySentryJsonConfiguration") {
                 into androidAssetsDir
                 rename { String fileName -> configFile }
             }
+
+            def sentryEnv = System.getenv('SENTRY_ENVIRONMENT')
+            if (sentryEnv) {
+                try {
+                    def destFile = new File(androidAssetsDir, configFile)
+                    def content = new groovy.json.JsonSlurper().parseText(destFile.text)
+                    content.environment = sentryEnv
+                    destFile.text = groovy.json.JsonOutput.toJson(content)
+                    logger.lifecycle("Overriding 'environment' from SENTRY_ENVIRONMENT environment variable")
+                } catch (Exception e) {
+                    logger.warn("Failed to override environment in ${configFile}: ${e.message}. Copied file as-is.")
+                }
+            }
             logger.lifecycle("Copied ${configFile} to Android assets")
         } else {
             logger.warn("${configFile} not found in app root (${appRoot})")
diff --git a/packages/core/test/scripts/sentry-xcode-scripts.test.ts b/packages/core/test/scripts/sentry-xcode-scripts.test.ts
index b9154fd752..ec0056fe7b 100644
--- a/packages/core/test/scripts/sentry-xcode-scripts.test.ts
+++ b/packages/core/test/scripts/sentry-xcode-scripts.test.ts
@@ -455,6 +455,103 @@ describe('sentry-xcode.sh', () => {
     expect(result.stdout).toContain('skipping sourcemaps upload');
   });
 
+  describe('sentry.options.json SENTRY_ENVIRONMENT override', () => {
+    it('copies file without modification when SENTRY_ENVIRONMENT is not set', () => {
+      const optionsContent = JSON.stringify({ dsn: 'https://key@sentry.io/123', environment: 'production' });
+      const optionsFile = path.join(tempDir, 'sentry.options.json');
+      fs.writeFileSync(optionsFile, optionsContent);
+
+      const buildDir = path.join(tempDir, 'build');
+      const resourcesPath = 'Resources';
+      fs.mkdirSync(path.join(buildDir, resourcesPath), { recursive: true });
+
+      const result = runScript({
+        SENTRY_DISABLE_AUTO_UPLOAD: 'true',
+        SENTRY_COPY_OPTIONS_FILE: 'true',
+        SENTRY_OPTIONS_FILE_PATH: optionsFile,
+        CONFIGURATION_BUILD_DIR: buildDir,
+        UNLOCALIZED_RESOURCES_FOLDER_PATH: resourcesPath,
+      });
+
+      expect(result.exitCode).toBe(0);
+      const destPath = path.join(buildDir, resourcesPath, 'sentry.options.json');
+      const copied = JSON.parse(fs.readFileSync(destPath, 'utf8'));
+      expect(copied.dsn).toBe('https://key@sentry.io/123');
+      expect(copied.environment).toBe('production');
+    });
+
+    it('overrides environment from SENTRY_ENVIRONMENT env var', () => {
+      const optionsContent = JSON.stringify({ dsn: 'https://key@sentry.io/123', environment: 'production' });
+      const optionsFile = path.join(tempDir, 'sentry.options.json');
+      fs.writeFileSync(optionsFile, optionsContent);
+
+      const buildDir = path.join(tempDir, 'build');
+      const resourcesPath = 'Resources';
+      fs.mkdirSync(path.join(buildDir, resourcesPath), { recursive: true });
+
+      const result = runScript({
+        SENTRY_DISABLE_AUTO_UPLOAD: 'true',
+        SENTRY_COPY_OPTIONS_FILE: 'true',
+        SENTRY_OPTIONS_FILE_PATH: optionsFile,
+        CONFIGURATION_BUILD_DIR: buildDir,
+        UNLOCALIZED_RESOURCES_FOLDER_PATH: resourcesPath,
+        SENTRY_ENVIRONMENT: 'staging',
+      });
+
+      expect(result.exitCode).toBe(0);
+      expect(result.stdout).toContain('Overriding');
+      const destPath = path.join(buildDir, resourcesPath, 'sentry.options.json');
+      const copied = JSON.parse(fs.readFileSync(destPath, 'utf8'));
+      expect(copied.environment).toBe('staging');
+      expect(copied.dsn).toBe('https://key@sentry.io/123');
+    });
+
+    it('does not modify the source sentry.options.json', () => {
+      const optionsContent = JSON.stringify({ dsn: 'https://key@sentry.io/123', environment: 'production' });
+      const optionsFile = path.join(tempDir, 'sentry.options.json');
+      fs.writeFileSync(optionsFile, optionsContent);
+
+      const buildDir = path.join(tempDir, 'build');
+      const resourcesPath = 'Resources';
+      fs.mkdirSync(path.join(buildDir, resourcesPath), { recursive: true });
+
+      runScript({
+        SENTRY_DISABLE_AUTO_UPLOAD: 'true',
+        SENTRY_COPY_OPTIONS_FILE: 'true',
+        SENTRY_OPTIONS_FILE_PATH: optionsFile,
+        CONFIGURATION_BUILD_DIR: buildDir,
+        UNLOCALIZED_RESOURCES_FOLDER_PATH: resourcesPath,
+        SENTRY_ENVIRONMENT: 'staging',
+      });
+
+      const source = JSON.parse(fs.readFileSync(optionsFile, 'utf8'));
+      expect(source.environment).toBe('production');
+    });
+
+    it('falls back to plain copy when sentry.options.json contains invalid JSON', () => {
+      const optionsFile = path.join(tempDir, 'sentry.options.json');
+      fs.writeFileSync(optionsFile, 'invalid json{{{');
+
+      const buildDir = path.join(tempDir, 'build');
+      const resourcesPath = 'Resources';
+      fs.mkdirSync(path.join(buildDir, resourcesPath), { recursive: true });
+
+      const result = runScript({
+        SENTRY_DISABLE_AUTO_UPLOAD: 'true',
+        SENTRY_COPY_OPTIONS_FILE: 'true',
+        SENTRY_OPTIONS_FILE_PATH: optionsFile,
+        CONFIGURATION_BUILD_DIR: buildDir,
+        UNLOCALIZED_RESOURCES_FOLDER_PATH: resourcesPath,
+        SENTRY_ENVIRONMENT: 'staging',
+      });
+
+      expect(result.exitCode).toBe(0);
+      const destPath = path.join(buildDir, resourcesPath, 'sentry.options.json');
+      expect(fs.readFileSync(destPath, 'utf8')).toBe('invalid json{{{');
+      expect(result.stdout).toContain('Copied');
+    });
+  });
+
   describe('SOURCEMAP_FILE path resolution', () => {
     // Returns a mock sentry-cli that prints the SOURCEMAP_FILE env var it received.
     const makeSourcemapEchoScript = (dir: string): string => {