diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index ef0ce5d..a817334 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "4.13.1"
+  ".": "4.14.0"
 }
\ No newline at end of file
diff --git a/.stats.yml b/.stats.yml
index effa635..a59050a 100644
--- a/.stats.yml
+++ b/.stats.yml
@@ -1,4 +1,4 @@
 configured_endpoints: 103
-openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/courier%2Fcourier-3f78581b4e078a1f620d9f587f18d77bcde6d20f56b0e4ae798648f4236494fb.yml
+openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/courier/courier-2fca943954773292b6ca82dcb420c6500d118d2fbbe1cd4718afcb804f6c818c.yml
 openapi_spec_hash: 6bd33e0396d85e11bb46f0d549af93a3
 config_hash: afcc4f6f8c33ca3f338589e32e086f56
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 21698c5..6340b3d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,13 @@
 # Changelog
 
+## 4.14.0 (2026-05-01)
+
+Full Changelog: [v4.13.1...v4.14.0](https://github.com/trycourier/courier-java/compare/v4.13.1...v4.14.0)
+
+### Features
+
+* support setting headers via env ([0daaeb0](https://github.com/trycourier/courier-java/commit/0daaeb00073c63b431948f08180a83ba8103e74a))
+
 ## 4.13.1 (2026-04-14)
 
 Full Changelog: [v4.13.0...v4.13.1](https://github.com/trycourier/courier-java/compare/v4.13.0...v4.13.1)
diff --git a/build.gradle.kts b/build.gradle.kts
index 5e5c1b3..8e274ff 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -8,7 +8,7 @@ repositories {
 
 allprojects {
     group = "com.courier"
-    version = "4.13.1" // x-release-please-version
+    version = "4.14.0" // x-release-please-version
 }
 
 subprojects {
diff --git a/courier-java-core/src/main/kotlin/com/courier/core/ClientOptions.kt b/courier-java-core/src/main/kotlin/com/courier/core/ClientOptions.kt
index bee2096..825ec1a 100644
--- a/courier-java-core/src/main/kotlin/com/courier/core/ClientOptions.kt
+++ b/courier-java-core/src/main/kotlin/com/courier/core/ClientOptions.kt
@@ -373,6 +373,14 @@ private constructor(
             (System.getProperty("courier.apiKey") ?: System.getenv("COURIER_API_KEY"))?.let {
                 apiKey(it)
             }
+            System.getenv("COURIER_CUSTOM_HEADERS")?.let { customHeadersEnv ->
+                for (line in customHeadersEnv.split("\n")) {
+                    val colon = line.indexOf(':')
+                    if (colon >= 0) {
+                        putHeader(line.substring(0, colon).trim(), line.substring(colon + 1).trim())
+                    }
+                }
+            }
         }
 
         /**