diff --git a/modules/openapi-generator/src/main/resources/go/client.mustache b/modules/openapi-generator/src/main/resources/go/client.mustache
index f1270b3c692d..2b43d4d1b317 100644
--- a/modules/openapi-generator/src/main/resources/go/client.mustache
+++ b/modules/openapi-generator/src/main/resources/go/client.mustache
@@ -172,7 +172,7 @@ func parameterAddToHeaderOrQuery(headerOrQueryParams interface{}, keyPrefix stri
 					return
 				}
 				if t, ok := obj.(time.Time); ok {
-					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339), collectionType)
+					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339Nano), collectionType)
 					return
 				}
 				value = v.Type().String() + " value"
diff --git a/samples/client/echo_api/go-external-refs/client.go b/samples/client/echo_api/go-external-refs/client.go
index fba23f940742..6c4adba09560 100644
--- a/samples/client/echo_api/go-external-refs/client.go
+++ b/samples/client/echo_api/go-external-refs/client.go
@@ -178,7 +178,7 @@ func parameterAddToHeaderOrQuery(headerOrQueryParams interface{}, keyPrefix stri
 					return
 				}
 				if t, ok := obj.(time.Time); ok {
-					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339), collectionType)
+					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339Nano), collectionType)
 					return
 				}
 				value = v.Type().String() + " value"
diff --git a/samples/client/echo_api/go/client.go b/samples/client/echo_api/go/client.go
index fba23f940742..6c4adba09560 100644
--- a/samples/client/echo_api/go/client.go
+++ b/samples/client/echo_api/go/client.go
@@ -178,7 +178,7 @@ func parameterAddToHeaderOrQuery(headerOrQueryParams interface{}, keyPrefix stri
 					return
 				}
 				if t, ok := obj.(time.Time); ok {
-					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339), collectionType)
+					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339Nano), collectionType)
 					return
 				}
 				value = v.Type().String() + " value"
diff --git a/samples/client/others/go/allof_multiple_ref_and_discriminator/client.go b/samples/client/others/go/allof_multiple_ref_and_discriminator/client.go
index f745e46a4268..7a054ad52eb7 100644
--- a/samples/client/others/go/allof_multiple_ref_and_discriminator/client.go
+++ b/samples/client/others/go/allof_multiple_ref_and_discriminator/client.go
@@ -159,7 +159,7 @@ func parameterAddToHeaderOrQuery(headerOrQueryParams interface{}, keyPrefix stri
 					return
 				}
 				if t, ok := obj.(time.Time); ok {
-					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339), collectionType)
+					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339Nano), collectionType)
 					return
 				}
 				value = v.Type().String() + " value"
diff --git a/samples/client/others/go/oneof-anyof-required/client.go b/samples/client/others/go/oneof-anyof-required/client.go
index f745e46a4268..7a054ad52eb7 100644
--- a/samples/client/others/go/oneof-anyof-required/client.go
+++ b/samples/client/others/go/oneof-anyof-required/client.go
@@ -159,7 +159,7 @@ func parameterAddToHeaderOrQuery(headerOrQueryParams interface{}, keyPrefix stri
 					return
 				}
 				if t, ok := obj.(time.Time); ok {
-					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339), collectionType)
+					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339Nano), collectionType)
 					return
 				}
 				value = v.Type().String() + " value"
diff --git a/samples/client/petstore/go/go-petstore/client.go b/samples/client/petstore/go/go-petstore/client.go
index 66cc7f921a41..c56879d3acae 100644
--- a/samples/client/petstore/go/go-petstore/client.go
+++ b/samples/client/petstore/go/go-petstore/client.go
@@ -178,7 +178,7 @@ func parameterAddToHeaderOrQuery(headerOrQueryParams interface{}, keyPrefix stri
 					return
 				}
 				if t, ok := obj.(time.Time); ok {
-					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339), collectionType)
+					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339Nano), collectionType)
 					return
 				}
 				value = v.Type().String() + " value"
diff --git a/samples/openapi3/client/extensions/x-auth-id-alias/go-experimental/client.go b/samples/openapi3/client/extensions/x-auth-id-alias/go-experimental/client.go
index 431577cfccd2..33da123ab61c 100644
--- a/samples/openapi3/client/extensions/x-auth-id-alias/go-experimental/client.go
+++ b/samples/openapi3/client/extensions/x-auth-id-alias/go-experimental/client.go
@@ -162,7 +162,7 @@ func parameterAddToHeaderOrQuery(headerOrQueryParams interface{}, keyPrefix stri
 					return
 				}
 				if t, ok := obj.(time.Time); ok {
-					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339), collectionType)
+					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339Nano), collectionType)
 					return
 				}
 				value = v.Type().String() + " value"
diff --git a/samples/openapi3/client/petstore/go-petstore-generateMarshalJSON-false/client.go b/samples/openapi3/client/petstore/go-petstore-generateMarshalJSON-false/client.go
index 27e965065246..3174a5c333ef 100644
--- a/samples/openapi3/client/petstore/go-petstore-generateMarshalJSON-false/client.go
+++ b/samples/openapi3/client/petstore/go-petstore-generateMarshalJSON-false/client.go
@@ -163,7 +163,7 @@ func parameterAddToHeaderOrQuery(headerOrQueryParams interface{}, keyPrefix stri
 					return
 				}
 				if t, ok := obj.(time.Time); ok {
-					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339), collectionType)
+					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339Nano), collectionType)
 					return
 				}
 				value = v.Type().String() + " value"
diff --git a/samples/openapi3/client/petstore/go/go-petstore/client.go b/samples/openapi3/client/petstore/go/go-petstore/client.go
index aab1677559dc..5950806508b2 100644
--- a/samples/openapi3/client/petstore/go/go-petstore/client.go
+++ b/samples/openapi3/client/petstore/go/go-petstore/client.go
@@ -181,7 +181,7 @@ func parameterAddToHeaderOrQuery(headerOrQueryParams interface{}, keyPrefix stri
 					return
 				}
 				if t, ok := obj.(time.Time); ok {
-					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339), collectionType)
+					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339Nano), collectionType)
 					return
 				}
 				value = v.Type().String() + " value"