diff --git a/changelog/@unreleased/pr-670.v2.yml b/changelog/@unreleased/pr-670.v2.yml
new file mode 100644
index 00000000..73f991b7
--- /dev/null
+++ b/changelog/@unreleased/pr-670.v2.yml
@@ -0,0 +1,5 @@
+type: improvement
+improvement:
+  description: Add Default:TooManyRequests error code
+  links:
+  - https://github.com/palantir/conjure-go-runtime/pull/670
diff --git a/conjure-go-contract/errors/error.go b/conjure-go-contract/errors/error.go
index a6cc89c9..b600322c 100644
--- a/conjure-go-contract/errors/error.go
+++ b/conjure-go-contract/errors/error.go
@@ -135,6 +135,16 @@ func IsRequestEntityTooLarge(err error) bool {
 	return isErrorOfType(err, DefaultRequestEntityTooLarge)
 }
 
+// WrapWithTooManyRequests returns new error instance of default too many requests type wrapping an existing error.
+func WrapWithTooManyRequests(cause error, parameters ...wparams.ParamStorer) Error {
+	return newGenericError(cause, DefaultTooManyRequests, wparams.NewParamStorer(parameters...))
+}
+
+// IsTooManyRequests returns true if an error is an instance of default too many requests.
+func IsTooManyRequests(err error) bool {
+	return isErrorOfType(err, DefaultTooManyRequests)
+}
+
 // NewFailedPrecondition returns new error instance of default failed precondition type.
 func NewFailedPrecondition(parameters ...wparams.ParamStorer) Error {
 	return newGenericError(nil, DefaultFailedPrecondition, wparams.NewParamStorer(parameters...))
diff --git a/conjure-go-contract/errors/error_code.go b/conjure-go-contract/errors/error_code.go
index ad614d3c..78bd3580 100644
--- a/conjure-go-contract/errors/error_code.go
+++ b/conjure-go-contract/errors/error_code.go
@@ -50,6 +50,8 @@ const (
 	Conflict
 	// RequestEntityTooLarge has status code 413 RequestEntityTooLarge.
 	RequestEntityTooLarge
+	// TooManyRequests has status code 429 TooManyRequests.
+	TooManyRequests
 	// FailedPrecondition has status code 500 InternalServerError.
 	FailedPrecondition
 	// Internal has status code 500 InternalServerError.
@@ -77,6 +79,8 @@ func (ec ErrorCode) StatusCode() int {
 		return http.StatusConflict
 	case RequestEntityTooLarge:
 		return http.StatusRequestEntityTooLarge
+	case TooManyRequests:
+		return http.StatusTooManyRequests
 	case FailedPrecondition:
 		return http.StatusInternalServerError
 	case Internal:
@@ -108,6 +112,8 @@ func (ec ErrorCode) String() string {
 		return "CONFLICT"
 	case RequestEntityTooLarge:
 		return "REQUEST_ENTITY_TOO_LARGE"
+	case TooManyRequests:
+		return "TOO_MANY_REQUESTS"
 	case FailedPrecondition:
 		return "FAILED_PRECONDITION"
 	case Internal:
@@ -142,6 +148,8 @@ func (ec *ErrorCode) UnmarshalText(data []byte) error {
 		*ec = Conflict
 	case "REQUEST_ENTITY_TOO_LARGE":
 		*ec = RequestEntityTooLarge
+	case "TOO_MANY_REQUESTS":
+		*ec = TooManyRequests
 	case "FAILED_PRECONDITION":
 		*ec = FailedPrecondition
 	case "INTERNAL":
diff --git a/conjure-go-contract/errors/error_code_test.go b/conjure-go-contract/errors/error_code_test.go
index 8f904493..c57ecce0 100644
--- a/conjure-go-contract/errors/error_code_test.go
+++ b/conjure-go-contract/errors/error_code_test.go
@@ -34,6 +34,7 @@ func TestErrorCode_String(t *testing.T) {
 		errors.NotFound:              "NOT_FOUND",
 		errors.Conflict:              "CONFLICT",
 		errors.RequestEntityTooLarge: "REQUEST_ENTITY_TOO_LARGE",
+		errors.TooManyRequests:       "TOO_MANY_REQUESTS",
 		errors.FailedPrecondition:    "FAILED_PRECONDITION",
 		errors.Internal:              "INTERNAL",
 		errors.Timeout:               "TIMEOUT",
@@ -53,6 +54,7 @@ var validErrorCodes = []errors.ErrorCode{
 	errors.NotFound,
 	errors.Conflict,
 	errors.RequestEntityTooLarge,
+	errors.TooManyRequests,
 	errors.FailedPrecondition,
 	errors.Internal,
 	errors.Timeout,
diff --git a/conjure-go-contract/errors/error_type.go b/conjure-go-contract/errors/error_type.go
index 2e9d7a04..eaf592a1 100644
--- a/conjure-go-contract/errors/error_type.go
+++ b/conjure-go-contract/errors/error_type.go
@@ -31,6 +31,7 @@ var (
 	DefaultNotFound              = ErrorType{NotFound, errorNameNotFound}
 	DefaultConflict              = ErrorType{Conflict, errorNameConflict}
 	DefaultRequestEntityTooLarge = ErrorType{RequestEntityTooLarge, errorNameRequestEntityTooLarge}
+	DefaultTooManyRequests       = ErrorType{TooManyRequests, errorNameTooManyRequests}
 	DefaultFailedPrecondition    = ErrorType{FailedPrecondition, errorNameFailedPrecondition}
 	DefaultInternal              = ErrorType{Internal, errorNameInternal}
 	DefaultTimeout               = ErrorType{Timeout, errorNameTimeout}
@@ -117,6 +118,7 @@ const (
 	errorNameNotFound              = "Default:NotFound"
 	errorNameConflict              = "Default:Conflict"
 	errorNameRequestEntityTooLarge = "Default:RequestEntityTooLarge"
+	errorNameTooManyRequests       = "Default:TooManyRequests"
 	errorNameFailedPrecondition    = "Default:FailedPrecondition"
 	errorNameInternal              = "Default:Internal"
 	errorNameTimeout               = "Default:Timeout"
@@ -134,6 +136,7 @@ func verifyErrorNameString(name string) error {
 		case errorNameNotFound:
 		case errorNameConflict:
 		case errorNameRequestEntityTooLarge:
+		case errorNameTooManyRequests:
 		case errorNameFailedPrecondition:
 		case errorNameInternal:
 		case errorNameTimeout:
@@ -154,6 +157,7 @@ func verifyErrorCodeErrorNameCombination(code ErrorCode, name string) error {
 		case DefaultNotFound:
 		case DefaultConflict:
 		case DefaultRequestEntityTooLarge:
+		case DefaultTooManyRequests:
 		case DefaultFailedPrecondition:
 		case DefaultInternal:
 		case DefaultTimeout: