diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index 1c8721128..4e142e6e8 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "0.526.0"
+  ".": "0.527.0"
 }
\ No newline at end of file
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9897f539f..cd911c133 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,13 @@
 # Changelog
 
+## 0.527.0 (2026-04-27)
+
+Full Changelog: [v0.526.0...v0.527.0](https://github.com/Increase/increase-java/compare/v0.526.0...v0.527.0)
+
+### Features
+
+* support setting headers via env ([18f9836](https://github.com/Increase/increase-java/commit/18f983666aefa0cee6b8fe89f75965f8ab52cc04))
+
 ## 0.526.0 (2026-04-27)
 
 Full Changelog: [v0.525.0...v0.526.0](https://github.com/Increase/increase-java/compare/v0.525.0...v0.526.0)
diff --git a/README.md b/README.md
index b80aeaff4..e81c77bbd 100644
--- a/README.md
+++ b/README.md
@@ -2,8 +2,8 @@
 
 <!-- x-release-please-start-version -->
 
-[![Maven Central](https://img.shields.io/maven-central/v/com.increase.api/increase-java)](https://central.sonatype.com/artifact/com.increase.api/increase-java/0.526.0)
-[![javadoc](https://javadoc.io/badge2/com.increase.api/increase-java/0.526.0/javadoc.svg)](https://javadoc.io/doc/com.increase.api/increase-java/0.526.0)
+[![Maven Central](https://img.shields.io/maven-central/v/com.increase.api/increase-java)](https://central.sonatype.com/artifact/com.increase.api/increase-java/0.527.0)
+[![javadoc](https://javadoc.io/badge2/com.increase.api/increase-java/0.527.0/javadoc.svg)](https://javadoc.io/doc/com.increase.api/increase-java/0.527.0)
 
 <!-- x-release-please-end -->
 
@@ -13,7 +13,7 @@ The Increase Java SDK is similar to the Increase Kotlin SDK but with minor diffe
 
 <!-- x-release-please-start-version -->
 
-The REST API documentation can be found on [increase.com](https://increase.com/documentation). Javadocs are available on [javadoc.io](https://javadoc.io/doc/com.increase.api/increase-java/0.526.0).
+The REST API documentation can be found on [increase.com](https://increase.com/documentation). Javadocs are available on [javadoc.io](https://javadoc.io/doc/com.increase.api/increase-java/0.527.0).
 
 <!-- x-release-please-end -->
 
@@ -24,7 +24,7 @@ The REST API documentation can be found on [increase.com](https://increase.com/d
 ### Gradle
 
 ```kotlin
-implementation("com.increase.api:increase-java:0.526.0")
+implementation("com.increase.api:increase-java:0.527.0")
 ```
 
 ### Maven
@@ -33,7 +33,7 @@ implementation("com.increase.api:increase-java:0.526.0")
 <dependency>
   <groupId>com.increase.api</groupId>
   <artifactId>increase-java</artifactId>
-  <version>0.526.0</version>
+  <version>0.527.0</version>
 </dependency>
 ```
 
diff --git a/build.gradle.kts b/build.gradle.kts
index 6696adc6b..b84ca2f80 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -8,7 +8,7 @@ repositories {
 
 allprojects {
     group = "com.increase.api"
-    version = "0.526.0" // x-release-please-version
+    version = "0.527.0" // x-release-please-version
 }
 
 subprojects {
diff --git a/increase-java-core/src/main/kotlin/com/increase/api/core/ClientOptions.kt b/increase-java-core/src/main/kotlin/com/increase/api/core/ClientOptions.kt
index a1a36135b..32ed9788c 100644
--- a/increase-java-core/src/main/kotlin/com/increase/api/core/ClientOptions.kt
+++ b/increase-java-core/src/main/kotlin/com/increase/api/core/ClientOptions.kt
@@ -429,6 +429,14 @@ private constructor(
             (System.getProperty("increase.webhookSecret")
                     ?: System.getenv("INCREASE_WEBHOOK_SECRET"))
                 ?.let { webhookSecret(it) }
+            System.getenv("INCREASE_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())
+                    }
+                }
+            }
         }
 
         /**