diff --git a/modules/openapi-generator/src/main/resources/kotlin-client/libraries/jvm-ktor/infrastructure/ApiClient.kt.mustache b/modules/openapi-generator/src/main/resources/kotlin-client/libraries/jvm-ktor/infrastructure/ApiClient.kt.mustache
index f8d10ef265e0..43542d634bcc 100644
--- a/modules/openapi-generator/src/main/resources/kotlin-client/libraries/jvm-ktor/infrastructure/ApiClient.kt.mustache
+++ b/modules/openapi-generator/src/main/resources/kotlin-client/libraries/jvm-ktor/infrastructure/ApiClient.kt.mustache
@@ -196,7 +196,7 @@ import {{packageName}}.auth.*
             }
             this.method = requestConfig.method.httpMethod
             headers.filter { header -> !UNSAFE_HEADERS.contains(header.key) }.forEach { header -> this.header(header.key, header.value) }
-            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH)) {
+            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH, RequestMethod.DELETE)) {
                 val contentType = (requestConfig.headers[HttpHeaders.ContentType]?.let { ContentType.parse(it) }
                     ?: ContentType.Application.Json)
                 this.contentType(contentType)
diff --git a/modules/openapi-generator/src/main/resources/kotlin-client/libraries/multiplatform/infrastructure/ApiClient.kt.mustache b/modules/openapi-generator/src/main/resources/kotlin-client/libraries/multiplatform/infrastructure/ApiClient.kt.mustache
index e82c2f3b6ae6..d2a1fe0ebf2e 100644
--- a/modules/openapi-generator/src/main/resources/kotlin-client/libraries/multiplatform/infrastructure/ApiClient.kt.mustache
+++ b/modules/openapi-generator/src/main/resources/kotlin-client/libraries/multiplatform/infrastructure/ApiClient.kt.mustache
@@ -166,7 +166,7 @@ import {{packageName}}.auth.*
             }
             this.method = requestConfig.method.httpMethod
             headers.filter { header -> !UNSAFE_HEADERS.contains(header.key) }.forEach { header -> this.header(header.key, header.value) }
-            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH)) {
+            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH, RequestMethod.DELETE)) {
                 val contentType = (requestConfig.headers[HttpHeaders.ContentType]?.let { ContentType.parse(it) }
                     ?: ContentType.Application.Json)
                 this.contentType(contentType)
diff --git a/samples/client/petstore/kotlin-array-nullable-items-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt b/samples/client/petstore/kotlin-array-nullable-items-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
index 081b4b08c51f..665fbb551381 100644
--- a/samples/client/petstore/kotlin-array-nullable-items-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
+++ b/samples/client/petstore/kotlin-array-nullable-items-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
@@ -155,7 +155,7 @@ open class ApiClient(
             }
             this.method = requestConfig.method.httpMethod
             headers.filter { header -> !UNSAFE_HEADERS.contains(header.key) }.forEach { header -> this.header(header.key, header.value) }
-            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH)) {
+            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH, RequestMethod.DELETE)) {
                 val contentType = (requestConfig.headers[HttpHeaders.ContentType]?.let { ContentType.parse(it) }
                     ?: ContentType.Application.Json)
                 this.contentType(contentType)
diff --git a/samples/client/petstore/kotlin-array-simple-string-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt b/samples/client/petstore/kotlin-array-simple-string-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
index 081b4b08c51f..665fbb551381 100644
--- a/samples/client/petstore/kotlin-array-simple-string-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
+++ b/samples/client/petstore/kotlin-array-simple-string-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
@@ -155,7 +155,7 @@ open class ApiClient(
             }
             this.method = requestConfig.method.httpMethod
             headers.filter { header -> !UNSAFE_HEADERS.contains(header.key) }.forEach { header -> this.header(header.key, header.value) }
-            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH)) {
+            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH, RequestMethod.DELETE)) {
                 val contentType = (requestConfig.headers[HttpHeaders.ContentType]?.let { ContentType.parse(it) }
                     ?: ContentType.Application.Json)
                 this.contentType(contentType)
diff --git a/samples/client/petstore/kotlin-bigdecimal-default-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt b/samples/client/petstore/kotlin-bigdecimal-default-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
index 081b4b08c51f..665fbb551381 100644
--- a/samples/client/petstore/kotlin-bigdecimal-default-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
+++ b/samples/client/petstore/kotlin-bigdecimal-default-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
@@ -155,7 +155,7 @@ open class ApiClient(
             }
             this.method = requestConfig.method.httpMethod
             headers.filter { header -> !UNSAFE_HEADERS.contains(header.key) }.forEach { header -> this.header(header.key, header.value) }
-            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH)) {
+            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH, RequestMethod.DELETE)) {
                 val contentType = (requestConfig.headers[HttpHeaders.ContentType]?.let { ContentType.parse(it) }
                     ?: ContentType.Application.Json)
                 this.contentType(contentType)
diff --git a/samples/client/petstore/kotlin-default-values-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt b/samples/client/petstore/kotlin-default-values-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
index 081b4b08c51f..665fbb551381 100644
--- a/samples/client/petstore/kotlin-default-values-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
+++ b/samples/client/petstore/kotlin-default-values-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
@@ -155,7 +155,7 @@ open class ApiClient(
             }
             this.method = requestConfig.method.httpMethod
             headers.filter { header -> !UNSAFE_HEADERS.contains(header.key) }.forEach { header -> this.header(header.key, header.value) }
-            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH)) {
+            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH, RequestMethod.DELETE)) {
                 val contentType = (requestConfig.headers[HttpHeaders.ContentType]?.let { ContentType.parse(it) }
                     ?: ContentType.Application.Json)
                 this.contentType(contentType)
diff --git a/samples/client/petstore/kotlin-enum-integers-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt b/samples/client/petstore/kotlin-enum-integers-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
index 081b4b08c51f..665fbb551381 100644
--- a/samples/client/petstore/kotlin-enum-integers-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
+++ b/samples/client/petstore/kotlin-enum-integers-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
@@ -155,7 +155,7 @@ open class ApiClient(
             }
             this.method = requestConfig.method.httpMethod
             headers.filter { header -> !UNSAFE_HEADERS.contains(header.key) }.forEach { header -> this.header(header.key, header.value) }
-            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH)) {
+            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH, RequestMethod.DELETE)) {
                 val contentType = (requestConfig.headers[HttpHeaders.ContentType]?.let { ContentType.parse(it) }
                     ?: ContentType.Application.Json)
                 this.contentType(contentType)
diff --git a/samples/client/petstore/kotlin-jvm-ktor-gson/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt b/samples/client/petstore/kotlin-jvm-ktor-gson/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
index 1a7ef603aec8..73906a5e50fa 100644
--- a/samples/client/petstore/kotlin-jvm-ktor-gson/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
+++ b/samples/client/petstore/kotlin-jvm-ktor-gson/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
@@ -156,7 +156,7 @@ open class ApiClient(
             }
             this.method = requestConfig.method.httpMethod
             headers.filter { header -> !UNSAFE_HEADERS.contains(header.key) }.forEach { header -> this.header(header.key, header.value) }
-            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH)) {
+            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH, RequestMethod.DELETE)) {
                 val contentType = (requestConfig.headers[HttpHeaders.ContentType]?.let { ContentType.parse(it) }
                     ?: ContentType.Application.Json)
                 this.contentType(contentType)
diff --git a/samples/client/petstore/kotlin-jvm-ktor-jackson/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt b/samples/client/petstore/kotlin-jvm-ktor-jackson/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
index 99428a2b686b..9e775011cdad 100644
--- a/samples/client/petstore/kotlin-jvm-ktor-jackson/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
+++ b/samples/client/petstore/kotlin-jvm-ktor-jackson/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
@@ -164,7 +164,7 @@ open class ApiClient(
             }
             this.method = requestConfig.method.httpMethod
             headers.filter { header -> !UNSAFE_HEADERS.contains(header.key) }.forEach { header -> this.header(header.key, header.value) }
-            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH)) {
+            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH, RequestMethod.DELETE)) {
                 val contentType = (requestConfig.headers[HttpHeaders.ContentType]?.let { ContentType.parse(it) }
                     ?: ContentType.Application.Json)
                 this.contentType(contentType)
diff --git a/samples/client/petstore/kotlin-jvm-ktor-kotlinx_serialization/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt b/samples/client/petstore/kotlin-jvm-ktor-kotlinx_serialization/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
index 13b6616e8f48..0211c0b29c28 100644
--- a/samples/client/petstore/kotlin-jvm-ktor-kotlinx_serialization/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
+++ b/samples/client/petstore/kotlin-jvm-ktor-kotlinx_serialization/src/main/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
@@ -147,7 +147,7 @@ open class ApiClient(
             }
             this.method = requestConfig.method.httpMethod
             headers.filter { header -> !UNSAFE_HEADERS.contains(header.key) }.forEach { header -> this.header(header.key, header.value) }
-            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH)) {
+            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH, RequestMethod.DELETE)) {
                 val contentType = (requestConfig.headers[HttpHeaders.ContentType]?.let { ContentType.parse(it) }
                     ?: ContentType.Application.Json)
                 this.contentType(contentType)
diff --git a/samples/client/petstore/kotlin-multiplatform-allOf-discriminator/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt b/samples/client/petstore/kotlin-multiplatform-allOf-discriminator/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
index 251e0249b307..e012f5d4152e 100644
--- a/samples/client/petstore/kotlin-multiplatform-allOf-discriminator/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
+++ b/samples/client/petstore/kotlin-multiplatform-allOf-discriminator/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
@@ -155,7 +155,7 @@ open class ApiClient(
             }
             this.method = requestConfig.method.httpMethod
             headers.filter { header -> !UNSAFE_HEADERS.contains(header.key) }.forEach { header -> this.header(header.key, header.value) }
-            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH)) {
+            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH, RequestMethod.DELETE)) {
                 val contentType = (requestConfig.headers[HttpHeaders.ContentType]?.let { ContentType.parse(it) }
                     ?: ContentType.Application.Json)
                 this.contentType(contentType)
diff --git a/samples/client/petstore/kotlin-multiplatform-kotlinx-datetime/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt b/samples/client/petstore/kotlin-multiplatform-kotlinx-datetime/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
index 838201aa9650..b1c981949e2a 100644
--- a/samples/client/petstore/kotlin-multiplatform-kotlinx-datetime/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
+++ b/samples/client/petstore/kotlin-multiplatform-kotlinx-datetime/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
@@ -159,7 +159,7 @@ open class ApiClient(
             }
             this.method = requestConfig.method.httpMethod
             headers.filter { header -> !UNSAFE_HEADERS.contains(header.key) }.forEach { header -> this.header(header.key, header.value) }
-            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH)) {
+            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH, RequestMethod.DELETE)) {
                 val contentType = (requestConfig.headers[HttpHeaders.ContentType]?.let { ContentType.parse(it) }
                     ?: ContentType.Application.Json)
                 this.contentType(contentType)
diff --git a/samples/client/petstore/kotlin-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt b/samples/client/petstore/kotlin-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
index 838201aa9650..b1c981949e2a 100644
--- a/samples/client/petstore/kotlin-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
+++ b/samples/client/petstore/kotlin-multiplatform/src/commonMain/kotlin/org/openapitools/client/infrastructure/ApiClient.kt
@@ -159,7 +159,7 @@ open class ApiClient(
             }
             this.method = requestConfig.method.httpMethod
             headers.filter { header -> !UNSAFE_HEADERS.contains(header.key) }.forEach { header -> this.header(header.key, header.value) }
-            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH)) {
+            if (requestConfig.method in listOf(RequestMethod.PUT, RequestMethod.POST, RequestMethod.PATCH, RequestMethod.DELETE)) {
                 val contentType = (requestConfig.headers[HttpHeaders.ContentType]?.let { ContentType.parse(it) }
                     ?: ContentType.Application.Json)
                 this.contentType(contentType)