diff --git a/packages/collector/src/index.js b/packages/collector/src/index.js
index 47bec9e9b3..cf3e557a9d 100644
--- a/packages/collector/src/index.js
+++ b/packages/collector/src/index.js
@@ -103,7 +103,7 @@ const instanaSharedMetrics = require('@instana/shared-metrics');
 require('./tracing'); // load additional instrumentations
 
 const log = require('./logger');
-const normalizeCollectorConfig = require('./util/normalizeConfig');
+const normalizeConfig = require('./util/normalizeConfig');
 const experimental = require('./experimental');
 
 // NOTE: Default collector logger && config for cases like `preinit`.
@@ -158,10 +158,10 @@ function init(userConfig = {}) {
     log.init(userConfig);
   }
 
-  const collectorConfig = normalizeCollectorConfig(userConfig);
+  const finalCollectorConfig = normalizeConfig(userConfig);
   config = instanaNodeJsCore.coreConfig.normalize({
     userConfig,
-    finalConfigBase: collectorConfig
+    finalConfigBase: finalCollectorConfig
   });
 
   agentConnection = require('./agentConnection');
diff --git a/packages/collector/src/util/normalizeConfig.js b/packages/collector/src/util/normalizeConfig.js
index 11e13a5254..61a176a7e7 100644
--- a/packages/collector/src/util/normalizeConfig.js
+++ b/packages/collector/src/util/normalizeConfig.js
@@ -3,10 +3,10 @@
  * (c) Copyright Instana Inc. and contributors 2019
  */
 
-/* eslint-disable dot-notation */
-
 'use strict';
 
+const util = require('@instana/core/src/config/util');
+
 const defaults = {
   agentHost: '127.0.0.1',
   agentPort: 42699,
@@ -16,38 +16,95 @@ const defaults = {
 
 /**
  * Merges the config that was passed to the init function with environment variables and default values.
- * @param {import('../types/collector').CollectorConfig} config
+ * @param {import('../types/collector').CollectorConfig} userConfig
  * @returns {import('../types/collector').CollectorConfig}
  */
-module.exports = function normalizeConfig(config = {}) {
-  config.agentHost = config.agentHost || process.env.INSTANA_AGENT_HOST || defaults.agentHost;
-  config.agentPort = config.agentPort || parseToPositiveInteger(process.env.INSTANA_AGENT_PORT, defaults.agentPort);
-  config.agentRequestTimeout =
-    config.agentRequestTimeout ||
-    parseToPositiveInteger(process.env.INSTANA_AGENT_REQUEST_TIMEOUT, defaults.agentRequestTimeout);
+module.exports = function normalizeConfig(userConfig = {}) {
+  const finalConfig = {};
 
-  config.autoProfile = config.autoProfile || process.env.INSTANA_AUTO_PROFILE || defaults.autoProfile;
-  config.tracing = config.tracing || {};
-
-  if (config.reportUnhandledPromiseRejections == null) {
-    config.reportUnhandledPromiseRejections = false;
-  }
+  // NOTE: This function only normalizes collector-specific configuration fields.
+  // Other userConfig fields (like serviceName, tracing, etc.) are passed through as-is
+  // and will be normalized later by core/config when this collector config is passed
+  // as extraFinalConfig to core's normalize function.
+  finalConfig.agentHost = normalizeAgentHost(userConfig, defaults);
+  finalConfig.agentPort = normalizeAgentPort(userConfig, defaults);
+  finalConfig.agentRequestTimeout = normalizeAgentRequestTimeout(userConfig, defaults);
+  finalConfig.autoProfile = normalizeAutoProfile(userConfig, defaults);
+  finalConfig.reportUnhandledPromiseRejections = normalizeUnhandledRejections(userConfig);
+  finalConfig.tracing = userConfig.tracing || {};
 
-  return config;
+  return finalConfig;
 };
 
 /**
- * @param {string | number} value
- * @param {number} defaultValue
+ * @param {import('../types/collector').CollectorConfig} userConfig
+ * @param {{ agentHost: string }} defaultConfig
+ * @returns {string}
+ */
+function normalizeAgentHost(userConfig, defaultConfig) {
+  return resolveConfig(process.env.INSTANA_AGENT_HOST, userConfig.agentHost, defaultConfig.agentHost);
+}
+
+/**
+ * @param {import('../types/collector').CollectorConfig} userConfig
+ * @param {{ agentPort: number }} defaultConfig
  * @returns {number}
  */
-function parseToPositiveInteger(value, defaultValue) {
-  if (typeof value !== 'string') {
-    return defaultValue;
+function normalizeAgentPort(userConfig, defaultConfig) {
+  return util.resolveNumericConfig({
+    envVar: 'INSTANA_AGENT_PORT',
+    configValue: userConfig.agentPort,
+    defaultValue: defaultConfig.agentPort,
+    configPath: 'config.agentPort'
+  });
+}
+
+/**
+ * @param {import('../types/collector').CollectorConfig} userConfig
+ * @param {{ agentRequestTimeout: number }} defaultConfig
+ * @returns {number}
+ */
+function normalizeAgentRequestTimeout(userConfig, defaultConfig) {
+  return util.resolveNumericConfig({
+    envVar: 'INSTANA_AGENT_REQUEST_TIMEOUT',
+    configValue: userConfig.agentRequestTimeout,
+    defaultValue: defaultConfig.agentRequestTimeout,
+    configPath: 'config.agentRequestTimeout'
+  });
+}
+
+/**
+ * @param {import('../types/collector').CollectorConfig} userConfig
+ * @param {{ autoProfile: string | boolean }} defaultConfig
+ * @returns {string | boolean}
+ */
+function normalizeAutoProfile(userConfig, defaultConfig) {
+  return resolveConfig(process.env.INSTANA_AUTO_PROFILE, userConfig.autoProfile, defaultConfig.autoProfile);
+}
+
+/**
+ * @param {import('../types/collector').CollectorConfig} userConfig
+ * @returns {boolean}
+ */
+function normalizeUnhandledRejections(userConfig) {
+  return userConfig.reportUnhandledPromiseRejections ?? false;
+}
+
+/**
+ * @template T
+ * @param {T | undefined} envValue
+ * @param {T | undefined} configValue
+ * @param {T} defaultValue
+ * @returns {T}
+ */
+function resolveConfig(envValue, configValue, defaultValue) {
+  if (configValue != null) {
+    return configValue;
   }
-  value = parseInt(value, 10);
-  if (!isNaN(value)) {
-    return Math.abs(Math.round(value));
+
+  if (envValue != null) {
+    return envValue;
   }
+
   return defaultValue;
 }
diff --git a/packages/collector/test/unit/src/util/normalizeConfig.test.js b/packages/collector/test/unit/src/util/normalizeConfig.test.js
index 9662fedbce..17497d9c25 100644
--- a/packages/collector/test/unit/src/util/normalizeConfig.test.js
+++ b/packages/collector/test/unit/src/util/normalizeConfig.test.js
@@ -6,10 +6,15 @@
 'use strict';
 
 const expect = require('chai').expect;
-
+const testUtils = require('@_local/core/test/test_util');
+const coreConfig = require('@instana/core/src/config');
 const normalizeConfig = require('@_local/collector/src/util/normalizeConfig');
 
 describe('util.normalizeConfig', () => {
+  before(() => {
+    coreConfig.init(testUtils.createFakeLogger());
+  });
+
   beforeEach(resetEnv);
   afterEach(resetEnv);
 
@@ -84,14 +89,6 @@ describe('util.normalizeConfig', () => {
       expect(config.agentPort).to.equal(42699);
     });
 
-    it('should normalize negative env values', () => {
-      process.env.INSTANA_AGENT_PORT = '-3000';
-
-      const config = normalizeConfig();
-
-      expect(config.agentPort).to.equal(3000);
-    });
-
     it('should fallback to default for invalid env value', () => {
       process.env.INSTANA_AGENT_PORT = 'invalid';