diff --git a/core/model/src/main/kotlin/au/com/dius/pact/core/model/OptionalBody.kt b/core/model/src/main/kotlin/au/com/dius/pact/core/model/OptionalBody.kt
index e50f34554..60f10c366 100644
--- a/core/model/src/main/kotlin/au/com/dius/pact/core/model/OptionalBody.kt
+++ b/core/model/src/main/kotlin/au/com/dius/pact/core/model/OptionalBody.kt
@@ -179,7 +179,7 @@ data class OptionalBody @JvmOverloads constructor(
             mapOf(
               "content" to JsonParser.parseString(valueAsString()),
               "contentType" to contentType.toString(),
-              "encoded" to "json"
+              "encoded" to false
             )
           } else {
             mapOf(
diff --git a/core/model/src/main/kotlin/au/com/dius/pact/core/model/V4Pact.kt b/core/model/src/main/kotlin/au/com/dius/pact/core/model/V4Pact.kt
index 28de57ea2..5cd76f349 100644
--- a/core/model/src/main/kotlin/au/com/dius/pact/core/model/V4Pact.kt
+++ b/core/model/src/main/kotlin/au/com/dius/pact/core/model/V4Pact.kt
@@ -48,7 +48,7 @@ fun bodyFromJson(field: String, json: JsonValue, headers: Map<String, Any>): Opt
 
         val (encoded, encoding) = if (jsonBody.has("encoded")) {
           when (val encodedValue = jsonBody["encoded"]) {
-            is JsonValue.StringValue -> true to encodedValue.toString()
+            is JsonValue.StringValue -> true to encodedValue.toString().lowercase()
             JsonValue.True -> true to "base64"
             else -> false to ""
           }
@@ -59,7 +59,7 @@ fun bodyFromJson(field: String, json: JsonValue, headers: Map<String, Any>): Opt
         val bodyBytes = if (encoded) {
           when (encoding) {
             "base64" -> Base64.getDecoder().decode(Json.toString(jsonBody["content"]))
-            "json" -> jsonBody["content"].serialise().toByteArray(contentType.asCharset())
+            "json" -> Json.toString(jsonBody["content"]).toByteArray(contentType.asCharset())
             else -> {
               logger.warn { "Unrecognised body encoding scheme '$encoding', will use the raw body" }
               Json.toString(jsonBody["content"]).toByteArray(contentType.asCharset())
diff --git a/core/model/src/test/groovy/au/com/dius/pact/core/model/OptionalBodySpec.groovy b/core/model/src/test/groovy/au/com/dius/pact/core/model/OptionalBodySpec.groovy
index 0dbbb72dc..ba5f9fd7f 100644
--- a/core/model/src/test/groovy/au/com/dius/pact/core/model/OptionalBodySpec.groovy
+++ b/core/model/src/test/groovy/au/com/dius/pact/core/model/OptionalBodySpec.groovy
@@ -163,8 +163,8 @@ class OptionalBodySpec extends Specification {
     body                                                                                                    | v4Format
     OptionalBody.missing()                                                                                  | [:]
     OptionalBody.body(''.bytes, ContentType.UNKNOWN)                                                        | [content: '']
-    OptionalBody.body('{}'.bytes, ContentType.UNKNOWN)                                                      | [content: new JsonValue.Object(), contentType: 'application/json', encoded: 'json']
-    OptionalBody.body('{}'.bytes, ContentType.JSON)                                                         | [content: new JsonValue.Object(), contentType: 'application/json', encoded: 'json']
+    OptionalBody.body('{}'.bytes, ContentType.UNKNOWN)                                                      | [content: new JsonValue.Object(), contentType: 'application/json', encoded: false]
+    OptionalBody.body('{}'.bytes, ContentType.JSON)                                                         | [content: new JsonValue.Object(), contentType: 'application/json', encoded: false]
     OptionalBody.body([0xff, 0xd8, 0xff, 0xe0] as byte[], new ContentType('image/jpeg'))                    | [content: '/9j/4A==', contentType: 'image/jpeg', encoded: 'base64', contentTypeHint: 'DEFAULT']
     OptionalBody.body('kjlkjlkjkl'.bytes, new ContentType('application/other'), ContentTypeHint.BINARY) | [content: 'a2psa2psa2prbA==', contentType: 'application/other', encoded: 'base64', contentTypeHint: 'BINARY']
   }
diff --git a/core/model/src/test/groovy/au/com/dius/pact/core/model/PactWriterSpec.groovy b/core/model/src/test/groovy/au/com/dius/pact/core/model/PactWriterSpec.groovy
index d4d43b005..f5bd3a520 100644
--- a/core/model/src/test/groovy/au/com/dius/pact/core/model/PactWriterSpec.groovy
+++ b/core/model/src/test/groovy/au/com/dius/pact/core/model/PactWriterSpec.groovy
@@ -345,7 +345,7 @@ class PactWriterSpec extends Specification {
     |        "contents": {
     |          "content": "this is a message",
     |          "contentType": "application/json",
-    |          "encoded": "json"
+    |          "encoded": false
     |        }
     |      },
     |      "response": [
@@ -353,7 +353,7 @@ class PactWriterSpec extends Specification {
     |          "contents": {
     |            "content": "this is a response",
     |            "contentType": "application/json",
-    |            "encoded": "json"
+    |            "encoded": false
     |          }
     |        }
     |      ],
diff --git a/core/model/src/test/groovy/au/com/dius/pact/core/model/V4PactKtSpec.groovy b/core/model/src/test/groovy/au/com/dius/pact/core/model/V4PactKtSpec.groovy
index 377493b5b..764422473 100644
--- a/core/model/src/test/groovy/au/com/dius/pact/core/model/V4PactKtSpec.groovy
+++ b/core/model/src/test/groovy/au/com/dius/pact/core/model/V4PactKtSpec.groovy
@@ -36,8 +36,11 @@ class V4PactKtSpec extends Specification {
     new JsonValue.Object([:])              | JsonValue.False.INSTANCE            | 'application/json' | OptionalBody.body('{}'.bytes, ContentType.JSON)
     new JsonValue.Object([:])              | JsonValue.False.INSTANCE            | ''                 | OptionalBody.body('{}'.bytes, ContentType.JSON)
     new JsonValue.StringValue('ABC')       | JsonValue.False.INSTANCE            | 'application/json' | OptionalBody.body('"ABC"'.bytes, ContentType.JSON)
-    new JsonValue.StringValue('ABC')       | new JsonValue.StringValue('json')   | 'application/json' | OptionalBody.body('"ABC"'.bytes, ContentType.JSON)
+    new JsonValue.StringValue('\"ABC\"')   | JsonValue.False.INSTANCE            | 'application/json' | OptionalBody.body('"\\"ABC\\""'.bytes, ContentType.JSON)
+    new JsonValue.StringValue('\"ABC\"')   | new JsonValue.StringValue('json')   | 'application/json' | OptionalBody.body('"ABC"'.bytes, ContentType.JSON)
+    new JsonValue.StringValue('\"ABC\"')   | new JsonValue.StringValue('JSON')   | 'application/json' | OptionalBody.body('"ABC"'.bytes, ContentType.JSON)
     new JsonValue.StringValue('IkFCQyI=')  | JsonValue.True.INSTANCE             | 'application/json' | OptionalBody.body('"ABC"'.bytes, ContentType.JSON)
     new JsonValue.StringValue('IkFCQyI=')  | new JsonValue.StringValue('base64') | 'application/json' | OptionalBody.body('"ABC"'.bytes, ContentType.JSON)
+    new JsonValue.StringValue('IkFCQyI=')  | new JsonValue.StringValue('BASE64') | 'application/json' | OptionalBody.body('"ABC"'.bytes, ContentType.JSON)
   }
 }